Iodine-131 reported in Tokyo — 10 sewage plants

[Joe Neubarth]

Iodine-131 reported in Tokyo — 10 of 12 sewage plants test positive in December

fukushima-diary.com/2011/12/breaking-news-increasing-leakag-of-iodine131/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+FukushimaDiary+%28Fukushima+Diary%29

Breaking news : Increasing leakage of Iodine131, Fukushima Diary, Dec. 27, 2011:

[...] In December, Iodine 131 was measured at 10 of 12 sewerage disposal plants in Tokyo. The samples are dehydration sludge, taken from 12/1~12/6.

[Joe Neubarth]

Iodine-131 (131I), also called radioiodine (though many other radioactive isotopes of this element are known), is an important radioisotope of iodine. It has a radioactive decay half-life of about eight days.

It also plays a major role as a radioactive isotope present in nuclear fission products, and was a significant contributor to the health hazards from open-air atomic bomb testing in the 1950s, and from the Chernobyl disaster, as well as being a large fraction of the contamination hazard in the first weeks in the Japanese nuclear crisis.

This is because I-131 is a major uranium, plutonium fission product, comprising nearly 3% of the total products of fission (by weight). See fission product yield for a comparison with other radioactive fission products. I-131 is also a major fission product of uranium-233, produced from thorium.

If we are getting substantial I-131 now, 300 days after the melt down, We are seeing proof of criticality in the reactor cores that are underground. Since the half life of I-131 is just a little over 8 days, after two months we should not be detecting significant I-131 any more. The fact that we are still detecting it over nine months later tells us that active fissioning it taking place at Fukushima.

We have 80 to 100 ton blobs of Corium in the earth and they are fissioning.