Wednesday, September 7, 2011

Radioactive Iodine in Sewer Sludge in Oshu City, Iwate

Oshu City is located 187 kilometers north of Fukushima I Nuclear Power Plant.

The city announced the latest survey of radioactive materials in sewer sludge in a sewage treatment center in the city, and it shows iodine-131 being detected in the sludge cake since August 25.

From the city's announcement on September 7 (original in Japanese, I translated the dates, etc.; emphasis is mine):

Collection date


Testing date


I-131

Cs-134

Cs-137

Cs-Total

7/7/2011

7/14/2011

ND

81

100

181

7/21/2011

7/23/2011

ND

71

64

135

7/28/2011

7/30/2011

ND

58

79

137

8/4/2011

8/7/2011

ND

38

76

114

8/11/2011

8/12/2011

ND

33

52

85

8/25/2011

8/27/2011

2,300

47

52

99

8/31/2011

9/2/2011

590

20

57

77

9/6/2011

9/6/2011

480

82

96

178


The city says it has stopped the shipment of sludge cakes from this plant because of the high radioactive iodine concentration detected from the August 25 sample, but that the sludge cakes have been used as fertilizer material because the amount of radioactive cesium has been below the provisional safety limit for composts and manures (400 becquerels/kg).

15 comments:

Anonymous said...

this is bad

Anonymous said...

Please forgive my confusion, but perhaps someone could elaborate on the implications of this test. 187K is a great distance, and Iodine has a short half life. How did this material reach Oshu City -- via wind and weather? Has the plant been processing debris from Fukushima? Is there perhaps a local source, other than Fukushima?

Mike

Anonymous said...

Iodine 131 has a half life of 8 days, so after a month or so it becomes almost undetectable. The presence of iodine 131 means that fission is still occurring and the reactors are not under control at all.

Anonymous said...

This means the nuclear fuel that has melted down at Fukushima Daichi or Daini is actively fissioning again. Uncontained nuclear fission releases massive amounts of heat and radioactivity into the atmosphere. If the levels are so high 170km from the plant, how much higher must they be nearer the plant? This is disastrous news.

People should be taking emergency potassium iodide medicine. This should be a top news story in all the media today.

Anonymous said...

this is indeed shocking, but could the Iodine comes from another (closer) nuclear plant?

Anonymous said...

Perhaps another "event" happened, one they are not telling the public about.

Anonymous said...

But why no increase in Cesium, if it would be from an ongoing fission process?

/Logicon

Kyotoresident said...

And why no iodine being detected in other areas closer to Fukushima?

Anonymous said...

Any word on testing the local population for exposure? If this is fallout from Fukushima it indicates an unbelievably massive amount of source material was deposited in the area. This could be due to a large rain out concentration during the initial release. It has been about 180 days since the accident that works out to 22.5 half life cycles. 10 half life cycles is generally considered enough decay for most emissions. Hopefully there is a different explanation because if it is 6 month old fallout the locals are in for major thyroid problems in the future.

Makes you wonder just how contaminated the ocean actually is since it got the majority of the dose.

Anonymous said...

On 18Aug, Morioka shi, Iwate ken had more than double normal background radiation for a couple hours, but the peak was only 0.06uSv/H.
Also on 18Aug, in Yuzawa shi, Akita ken, the background was double normal at 0.11uSv/H.
Could there have been a corium event near this time frame that resulted in elevated I131?

Lantzelot said...

Just looking at the time trends for Cs-137 and Cs-134 indicates that this is probably something else. If you have release of I-131 as a result of fission (i.e. from a nuclear reactor) you tend to have increased levels from the cesium isotopes as well. At another entry on this blog somebody linked to the CTBTO data for I-131 and Cs-137, there the peaks correlate very well for both isotopes:
I-131: http://www.bfs.de/de/ion/imis/ctbto_aktivitaetskonzentrationen_jod.gif
Cs-137: http://www.bfs.de/de/ion/imis/ctbto_aktivitaetskonzentrationen_caesium.gif

It should be pointed out that they do have different melting and boiling temperatures (Iodine melts at 114 degrees C and boils at 184 deg C, Cesium melts at 28 deg C and boils at 671 deg C), which of course affects how much is released of each in liquid or gas form. So one could imagine scenarios where only Iodine is released when the temperature is not high enough to release significant amounts of Cesium. But it would show up at other places as well, are there any data?

My first guess was releases from any medical facility where I-131 is used for treatment. But then there would be continuous releases, this started suddenly (would be interesting to see older data).

So it could in fact be from a single patient, returning from a hospital in another city, going to the toilet. During an I-131 treatment the activity ingested is of the order of GBq, i.e. one billion Bq. The patient will excrete about half of that within the first 24 hours, and the urine may have an activity of several hundred kBq/ml. It would take several hundred cubic meters of water to dilute it to the observed levels in the sewage sludge, which is what happens when the urine goes through the sewer system.

My five yen...

Anonymous said...

.
Note that 18.08.2011 -measurements are deleted from this chart ... iodine could be 9.200 or more (if you compare how the figure has fallen to 1/4 after one week.)

But where are the Fukushima radiators Strontim Plutonium etc other rad release figures?

How lucky we Euro-beans are: here we have one dangerous shaky leaking scary sarcophagus in Chernobyl.

Instead, Japanese are lucky, arent they? No such leaky problims; only four melted stable steam blobs drilling right into the water table...

Fukushima must be 4x safer, right?

see more http://wp.me/pwIAV-19

.

Anonymous said...

.
Plus+ The very high jump from ND = ZERO from Aug.11 to 2.300 means that the globe irradiating depop fukuradwinds shifted to north.

The measurement figures Aug.18 must have been terribleses - no other reason for this typical CO2-hoax-deletion.

Pregnant women are being shoved into Chrenobyl surpassing rad:
http://preparator.files.wordpress.com/2011/05/fukurad-babyscare10s.jpg?w=693&h=1604

Note: Chernobyl limit: 0.57 microsievertis/h = 5 microsievertis/year

see more http://wp.me/pwIAV-19

Goto11 said...

Tepco data shows I-131 at around 1.0E+02 Bq/L on August 9 in Unit 2 seawater intake canal (Tepco PDF - http://bit.ly/nR3aeA). This appears to be higher than previous measurements.

Anonymous said...

beef again ...

http://mdn.mainichi.jp/mdnnews/news/20110908p2g00m0dm107000c.html

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