(Abstract)
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 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 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 β nuclide, Strontium and αnuclide,
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 on α nuclide isotopes.
[Suspicion] Tepco stated they won’t analyze leaking water
for α nuclide “by mistake” Posted by Mochizuki on April 15th, 2013 http://fukushima-diary.com/2013/04/suspicion-tepco-stated-they-wont-analyze-leaking-water-for-%CE%B1-nuclide-by-mistake/
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) http://www.youtube.com/watch?vhs=1&v=-BKA9it2CWE&feature=player_detailpage#
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. http://radioactivity.nsr.go.jp/ja/contents/7000/6030/24/5600_0821.pdf
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 defferent 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.
http://www.mext.go.jp/b_menu/shingi/chousa/gijyutu/017/shiryo/__icsFiles/afieldfile/2011/10/05/1311753_3.pdf 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)
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