Posts Tagged ‘iodine’

Mainichi Shimbun reported further issues at Genkai Nuclear Power Plant in Kyushu. The water leaks follow those at Mihama and Fukushima Nuclear Power Plant last week and a fire yesterday at Tsuruga Nuclear Power Plant (read about it in Fire And Water At Japanese Nuclear Power Plants on Survival Japan). Previous update is available here. It mentioned that there hadn’t been any radioactive material leak, which of course was inexact (although KEPCO tries hard to prove there is no causal link between the leaks and the radiation surge) – incidentally JAPC declared the same regarding Tsuruga today.

About Genkai, claims by the local government that radiation levels ″sometimes rises under natural conditions such as rain″ might be half-truths as radioactive rains are not natural conditions, but it is irrelevant nonetheless in the current nuclear power plant leak context. Besides, ″the usual range of 433 to 472 cpm″ is not harmless – it is about 10 times readings I measured elsewhere in Japan (Cf. Geiger Counter Case Study: Inspector Alert on SurvivalJapan – although results in the post are given in uS/h, in fact 40 cpm was a typical value).

Nuclear power plants in “normal operation” in the US leak a ″little″ amount of radioactivity which operators must report to the NRC. Japanese nuclear power plants are similar although I am not aware of any such reporting in Japan.

Mainichi Shimbun – Radiation rose slightly afterwater leak at Genkai plant

SAGA, Japan (Kyodo) — A radiation reading at Kyushu Electric Power Co.’s Genkai nuclear power plant in Saga Prefecture rose slightly above the usual range after coolant water leaked there Friday, the prefectural government said Sunday.

The reading at an outlet for seawater cooling the No. 3 reactor’s secondary cooling system was 473 counts per minute at 3 p.m. Friday, against the usual range of 433 to 472 cpm, not high enough to immediately impact human health, it said.

On Friday morning, 1.8 tons of primary coolant water containing radioactive materials leaked within the reactor’s purification system. The utility claimed the radiation reading is unrelated to that leak and said it will investigate the cause.

Water used in treating low-level radioactive waste is sometimes discharged from the outlet, but that was not the case Friday, the local government said, adding the reading sometimes rises under natural conditions such as rain.

(Mainichi Japan) December 12, 2011

Original article may still be available at this link.

Further updates with “not so slight levels” or such as “Yukio Edano ordered the last Genkai reactor to shut down” for instance are foreseeable.


Fukushima is the primary source of atmospheric radioactive material fallout. Radioiodine, which disappears rapidly, is regularly detected and shows that criticallity is still happening. Melt-through in three reactors and total lack of control and knowledge about conditions by TEPCO would make it at least three times worse as Chernobyl – yet this has still to become common sense and most people in north-eastern Japan try to reassure themselves that it is still safe until the fourth reactor blows up, which is only a matter of time. Tokyo should have been evacuated immediately and forever – after 8 months, an orderly evacuation could have been carried out and housing built but the Japanese government and mostly the population, who lives in denial, decided otherwise.

Usually SurvivalJapan leaves Tokyo out of the picture as anyone serious about their survival in Japan would have left the no man’s land area, including Tokyo, long ago. However, M. Goshi Hosono’s plan to spread radiation all over Japan is making its way, with potential effects outside the no man’s land, in what we call the monitored land, as can be read in the Japan Today article below and which was already mentioned on SurvivalJapan almost 3 months ago in Tokyo Imports 500,000,000 Kg Of Nuclear Waste.

Incinerators are less than 4 miles away from the Imperial Palace and popular places like Shibuya and Ebisu, which will all be under the radioactive fallout when winds abate.

I am told that yakuza are different from other similar organizations worldwide, as they supposedly appeared first to protect outcasts and organize work for them, and are nationalists who want to protect Japan and the Imperial Family. Mothers who occupy Hibiya Park in Tokyo (close to the Parliament, the Imperial Palace and headquarters of many large dysfunctional companies such as TEPCO and neighbor Mizuho) reported that harassment from right-wing militia somewhat relented when mothers told them that they would pack up their camping tents and leave if His Majesty would meet with them and ask them to. There are a few public enemies in the government, firms and media nowadays who are jeopardizing Imperial lives and the future of Japan – one can only wonder what yakuza associations are waiting for before saving this country if nobody else will, not that I am suggesting anything.

Winds will carry radioactive smog towards Chiba peninsula and Izu peninsula and archipelago depending on the season and weather. Winds seldom blow west but they occasionnally do, as Meteocentrale wind simulations show, and they sometimes even reach Osaka from Fukushima. The flying distance between Tokyo to Osaka (250 miles) is about the same order as between Fukushima to Tokyo (150 miles), although slightly less and Tokyo is a secundary source, not exactly like Fukushima itself.

Besides, the terrain configuration around Tokyo, i.e. the Kanto Plain, is unfortunately perfect to drive radiation fallout as we surmised from March eleven and was later proven by the presence of hotspots in Gunma, Saitama, etc. Further west, the region of Nagoya, in Aichi prefecture, will be also affected as well as the whole Nobi Plain, although less than the Kanto Plain of course. The whole coastal area between Tokyo and Nagoya, i.e. Shizuoka, etc. will be on the way on adverse days. Radioactive winds can also easily go through between Shiga and Mie prefectures, where mountains are low and several valleys let highways through to Osaka.

Japan Today – Tsunami debris from Miyagi to be incinerated in Tokyo this week

Dec. 13, 2011 –


The first load of tsunami debris from Miyagi Prefecture will be test burned at a waste incineration plant in Tokyo’s Ota Ward on Tuesday and Wednesday, with further tests scheduled for Dec 20-21 at a Shinagawa Ward plant.

If the test burns go well, large-scale burning will commence next February at a rate of 150 tons per day, Tokyo metropolitan government officials said, Fuji TV reported. Under the plan, 10,000 tons of combustible debris from Onagawa will be disposed of in incineration facilities located on reclaimed land in the Tokyo Bay area.

Officials plan to burn 500,000 tons by 2013.

Miyagi, Iwate and Fukushima prefectures have massive mountains of rubble, said to weigh more than 23 million tons.

The debris being sent to Tokyo is mainly wood and metal. By the end of next March, Tokyo will have received a total of 500,000 tons of debris from Miyagi and Iwate prefectures.

This article may still be available from its original source.

This post is an update of Geiger Counter Case Study: Inspector Alert published on SurvivalJapan in which some questions remained open, mainly about the relatively high values (although still in the safe range) which I measured with the system kindly lent to me by Safecast and from whom I received some further advice.

The Safecast bGeigie system is designed to measure mainly gamma rays (high energy protons, akin to X-rays) and hence is used at least one meter above ground in their radiation maps. Since I live in the monitored land, several hundred miles away from Fukushima, gamma radiation is low and not really a concern. Therefore I had measured instead beta radiation (high energy electrons or positrons which are emitted back from the ground after radioactive fall-out) at about one foot above ground. For convenience, I monitored the level of radiation with the Safecast display which communicates by radio with the Inspector Alert safely cast in its lunchbox style (in Japanese “bento”) box, along with the GPS and SD memory card to geo-locate and store results. The Safecast team advised against this methodology for beta radiation pick-up and advised me to use the Inspector Alert alone for that matter – which I did.

I read the user manual to set the Inspector Alert display in uSv/h as opposed to CPM (count per minute) as I am more familiar with this unit and it is more relevant for body effects. The user manual explains that the factor used by the device to convert CPM into uSv/h is based on Cesium-137, the radionuclide used for its calibration, so the uSv/hr display is less accurate for other nuclides (such as Cesium-134, Strontium-90, Iodine-131 and of course Uranium and Plutonium…). This is why Safecast uses the CPM raw data instead.

The first measure that I made was inside my home and the display changed widely even in a single place. A Geiger counter is not like a weighing scale: it does not give a result at once nor does it give a stable result. Therefore when a value is broadcast either by citizens or a governmental organization, it should be taken with a grain of salt. For instance, I could measure 0.120 uSv/h and any value between 0.090 and 0.150 uSv/h, that is about 25% more or less than the central value. Sometimes, some wilder values would come up: how do we interpret these?

Radiation is a random phenomenon which occurs naturally, so when a particle hits the Geiger counter sensor plate, it is registered and changes the overall measure value. The Inspector Alert averages measures over 30 seconds in order to get a more statistically relevant measure. Even then, the result is only displayed every 3 seconds so if one is moving, there is a delay between the measure and the display. Then there is the 15% accuracy which is probably an average: it means that some wild values (standard deviation) can occur from time to time. Other factors which can affect the results are solar flares (there was just a sunstorm by the way) and, probably, thermal drift if the device electronics is not properly compensated when temperature changes (any kind of electronics sensor is subject to this phenomenon). The bottom line is that measures could be twice as high depending on temperature, solar activity, randomness of natural radioactivity, types of radionuclides (including artificial ones from nuclear plants) and radiation (here it is a synthetic result of alpha, beta, gamma and X-rays), accuracy, resolution, etc.

Indeed, I could still measure inside and outside values from 0.055 to 0.225 uSv/h and even up to 0.355 uSv/h when spot on granite blocks which are naturally radioactive. These new measures were consistent with the range I had already measured with the full Safecast system. I could also check that the outer casing of Safecast suitcase and bento box did not emit stronger radiation than the room so the Geiger counter is likely not contaminated (and there should not be any calibration issue either according to the user manual).

I still could not double-check with another type of Geiger counter yet but these new results convinced me that they are normal. The maximum international value (except in post-Fukushima Japan) accepted is 1 mSv/year, which equates to 0.114 uSv/h. Given a 15% accuracy, it means that the Inspector Alert should read between 0.097 and 0.131 uSv/h which is indeed what it does most of the time (so we can dismiss occasional lower and higher results as products of standard deviation).

A final word of advice which I received from Safecast and which is also documented in the user manual is to use the timed count function of the Inspector Alert over at least 10 minutes to further smooth out results. There should be about 15% difference maximum between two such timed counts.

I hope that this update helps you to get a better idea about the capabilities and limitations of Geiger counters in general and specifically of the Inspector Alert – and of the analytical mindset and of the basic radiation knowledge necessary to properly use them. In any case, purchasing a Geiger counter to try and measure radioactivity in food does not make any sense (unless the food is irradiated to such a level that just staring at it is dangerous) and that monitoring the food trace is a safer and more reliable procedure. Thankfully, this is getting easier.

Kyodo News reported today that a Genkai nuclear power plant reactor in Saga prefecture, Kyushu, was stopped due to an “abnormality”.

This coincides with a post on Fukushima Diary blog where radioiodine level in dehydrated sludge of Nagasaki city central sewage treatment plant (中部下水処理場) was reported much higher than in no man’s land Miyagi last month :

1) in Miyagi

  • 42 Bq/kg – 8/9/2011
  • 41 Bq/kg – 9/6/2011

2) In Nagasaki

  • 563 Bq/kg – 8/4/2011
  • 151 Bq/kg – 8/11/2011
  • 44 Bq/kg – 8/22/2011

Radioiodine disappears quickly so this comes from “fresh” nuclear reactions (half-life is about 8 days).

Of course, Kyushu Electric Power denied any radiation leak in the Kyodo article.

Genkai nuclear power plant is located near an island named Fukushima (sic) and the readings for Nagasaki city above are from about 60 km away as can be seen on the map of Kyushu below (Kyushu is the large southern island in our monitored land). The letter ‘A’ marker in purple locates Genkai and the red one Nagasaki city. (more…)

Paper masks are popular with Japanese and were recommended as a basic protective gear in the wake of 3-11. Foreign visitors usually mistake their purpose thanks to sensational TV programs about a supposedly higher pollution in Tokyo. Paper masks fill in fact multiple purposes, from allergy in-filter, flu virus out-filter, mouth humidifier, sexual harassment dissuasion, etc. Wearing a paper mask is among one of the last Japanese customs that foreigners adopt and I confess that I’m one of those who find it quite ridiculous to wear, especially for an expat. In fact, back in March, my family bought a pack and we did not use it. Another Japanese cultural idiosyncrasy that TV programs love to put on stage is the almost pathological fear of bacterial contamination, with some people wearing protective gloves and disinfectant spray bottles everywhere. Actually, I doubt most Japanese like shaking hands as westerners do. So it is highly surprising that a majority of Japanese seem unconcerned with radioactivity when they loath germs. This blog is not about cultural differences so I’ll make it short: wearing paper masks and latex gloves is not so ridiculous in my opinion anymore, especially if you live in the no man’s land and cannot leave (i.e. including Greater Tokyo, cf. Japan Livability Map September 2011 in SurvivalJapan), but also in the monitored land when radiation fall-out warnings are issued. Inhaling radioactive particles is a health hazard. Washing hands and even gargling / spitting when returning home is often seen at Japanese homes and I recommend it too, in order to avoid ingestion of contaminated dust. Hydrogen gas emission in Fukushima, radioiodine detection and yellow powdered-rain reports all point out to a new criticality in Fukushima without any reactor confinement and a lost corium this time so these basic protective measures are relevant (Cf. Fukushima in Recriticality and Typhoon Roke Aftermath In Fukushima in SurvivalJapan).

Meteocentrale website forecast for radiation dispersion is clear for Tokyo except from Monday evening as can be seen on the screenshot below. Fukushima plumes will cover the whole Kanto area from a low altitude. This forecast is based upon the assumption of typhoon 16 moving northeasterly as currently predicted by the Japanese Meteorological Agency. Any change in its course will divert fall-out carried winds. The renewal of short-lived Iodine-131 has been interpreted as a renewed criticallity in Fukushima, although of course officially denied (Cf. Fukushima in Recriticality ? in SurvivalJapan). Hence tomorrow’s fall-out may include more than just the usual Cesium. (more…)