(Extract)
The most recent report on the leakage problem said that about 22 liters of radioactive water had leaked from gaps between the pipes used to transfer it from underground water storage tank into an another tank, and that the level of radioactivity in the water was 290,000Bq/m3.
This is so high that the leakage is unsafe to approach. Prof. Koide commented that according to Japanese law, the safety level of radioactive water that can be discharged into the environment is 0.05Bq/m3, or 0./03Bq/m3 if it contains strontium, so it is easy to imagine how high 290,000Bq/m3 actually is!
Dousing it or injecting it with water is the only way of continuing to cool the molten fuel, and this requires 400tons of water every day. Prof. Koide also observed that the leaks will carry on for as long as Tepco keeps using water to cool the molten fuel, possibly for at least 40 more years, or as long as it takes to decommission the plant.
He also commented that although Tepco keeps making new tanks to combat the problem, this solution would not work for ever, and urged the company again to bring a tanker to store the water.
On top of the reported leakage problems, Prof. Koide reckons that there must have been many cracks in many different places in the trenches and pits and also in the concrete basements of the reactor and turbine buildings, which must have been damaged by the M9 earthquake in March 2011.
He has kept on advising right from the beginning that Tepco should have arranged to bring a tanker to store the contaminated water and should have built a huge underground dam to stop it leaking into the environment. However Tepco has never followed his advice, citing cost as one of the reasons.
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It looks like a never ending problem! One source said that these problems will mean a greater chance of TEPCO having to dump untreated contaminated water into the sea.
It looks like leaking has been always happening anyway, and it became an apparent problem as the tanks and the pipes started to leak.
The underground tanks were meant to store low level of radioactive water after being filtered through ALPS. But they have been using them to store high level of radioactive water (including the β (beta) emitting nuclide, Strontium and the α (alpha)emitting nuclide, Plutonium).
Tepco has been trying to get ALPS to work for some time but it’s still in its trial stage. ALPS is supposed to filter 62 radioactive nuclides. However Tepco seems not wanting to mention the α (alpha) emitting nuclide isotopes.
[Suspicion] Tepco stated they won’t analyze leaking water for the α emitting nuclide “by mistake” Posted by Mochizuki on April 15th, 2013
According to Mr. Koichi Oyama, a member of city council of Minami soma-city, Uranium fuel at Reactor 3 was consisting of 9% of Plutonium(MOX). He shows a list of ionizing radiations that were discharged from the crippled plant in the video below.(9m45s)
An interview with Mr. Koichi Oyama from Minamisoma (Oct.2011)
in the video at 9m45s Mr. Oyama shows four kinds of plutonium isotopes that were observed. But in press conference held by Ministry of Education, Culture, Sports, Science and Technology on Sep.30th, 2011 just three of them were brought to light.
The last one was plutonium241, which had radiation dose about 50 times as much as the total of the other three(PU238, PU239 & PU240).
A Plutonium contamination map by MEXT published on 12/8/12.
On Page7-10, is a list of the report on sixty one different locations in Fukushima, Miyagi, Ibaragi and Tochigi prefectures spanning a radius of 80km of the crippled plant.
Extract…
[…Prefecture – city/town/village – 緯度 latitude – 経度 longitude – PU241(lower limit of detection)-…]
You can see that different lower limit of detection have been applied, therefore..
“No Detection” does not mean that there are no isotopes! On page11 only the places they detected more than the lower limit of detection level were marked.
by MEXT on 30/9/11
Half life: PU238(88y) decays into PU234(245,000y), PU239(24,100y), PU240(6,600y), PU241(13.2y) decays into Am241(=silver, 433y)
Multi-nuclide Removal Equipment (ALPS)
(Reference) http://blog.goo.ne.jp/tarutaru22/e/a8f8b3e66c246ef3c3df8699b3a2ec45http://home.hiroshima-u.ac.jp/er/ReneN_P_P1.html
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