[ RadSafe ] Manchester University Study - New evidence of nuclear fuel releases found at Fukushima

[Roger Helbig]

http://www.manchester.ac.uk/discover/news/new-evidence-of-nuclear-fuel-releases-found-at-fukushima/
is original Manchester University article

New evidence of nuclear fuel releases found at Fukushima

by dunrenard
February 28, 2018

"Our research strongly suggests there is a need for further detailed
investigation on Fukushima fuel debris, inside, and potentially outside the
nuclear exclusion zone," said Dr Gareth Law.

Uranium and other radioactive materials, such as caesium and technetium,
have been found in tiny particles released from the damaged Fukushima
Daiichi nuclear reactors.
This could mean the environmental impact from the fallout may last much
longer than previously expected according to a new study by a team of
international researchers, including scientists from The University of
Manchester.
The team says that, for the first time, the fallout of Fukushima Daiichi
nuclear reactor fuel debris into the surrounding environment has been
"explicitly revealed" by the study.
The scientists have been looking at extremely small pieces of debris, known
as micro-particles, which were released into the environment during the
initial disaster in 2011. The researchers discovered uranium from nuclear
fuel embedded in or associated with caesium-rich micro particles that were
emitted from the plant's reactors during the meltdowns. The particles found
measure just five micrometres or less; approximately 20 times smaller than
the width of a human hair. The size of the particles means humans could
inhale them.
The reactor debris fragments were found inside the nuclear exclusion zone,
in paddy soils and at an abandoned aquaculture centre, located several
kilometres from the nuclear plant.
It was previously thought that only volatile, gaseous radionuclides such as
caesium and iodine were released from the damaged reactors. Now it is
becoming clear that small, solid particles were also emitted, and that some
of these particles contain very long-lived radionuclides; for example,
uranium has a half-life of billions of years.
Dr Gareth Law, Senior Lecturer in Analytical Radiochemistry at the
University of Manchester and an author on the paper, says: "Our research
strongly suggests there is a need for further detailed investigation on
Fukushima fuel debris, inside, and potentially outside the nuclear
exclusion zone. Whilst it is extremely difficult to get samples from such
an inhospitable environment, further work will enhance our understanding of
the long-term behaviour of the fuel debris nano-particles and their impact."
The Tokyo Electric Power Company (TEPCO) is currently responsible for the
clean-up and decommissioning process at the Fukushima Daiichi site and in
the surrounding exclusion zone. Dr Satoshi Utsunomiya, Associate Professor
at Kyushu University (Japan) led the study.
He added: "Having better knowledge of the released microparticles is also
vitally important as it provides much needed data on the status of the
melted nuclear fuels in the damaged reactors. This will provide extremely
useful information for TEPCO's decommissioning strategy."
At present, chemical data on the fuel debris located within the damaged
nuclear reactors is impossible to get due to the high levels of radiation.
The microparticles found by the international team of researchers will
provide vital clues on the decommissioning challenges that lie ahead.

Story Source:
Materials provided by Manchester University. Note: Content may be edited
for style and length.

Journal Reference:
1. Asumi Ochiai, Junpei Imoto, Mizuki Suetake, Tatsuki Komiya, Genki
Furuki, Ryohei Ikehara, Shinya Yamasaki, Gareth T. W. Law, Toshihiko
Ohnuki, Bernd Grambow, Rodney C. Ewing, Satoshi Utsunomiya. Uranium
Dioxides and Debris Fragments Released to the Environment with Cesium-Rich
Microparticles from the Fukushima Daiichi Nuclear Power Plant.
Environmental Science & Technology, 2018; DOI: 10.1021/acs.est.7b06309

Source : https://www.sciencedaily.com/releases/2018/02/180228092241.htm

dunrenard | March 1, 2018 at 3:55 am | Tags: Contamination, Fukushima
Radiation, Microparticles, Nuclear Fuel | Categories: Fukushima 2018 | URL:
https://wp.me/phgse-zmW

http://nuclear-news.net/2018/03/01/new-evidence-of-nuclear-fuel-releases-found-at-fukushima/