Page 63 - July-August 2012
Basic HTML Version
Nuclear Plant Journal, July-August 2012
63
system, with the aim of continuously
enhancing nuclear safety.
In
the
nuclear
emergency
preparedness and response area, the
introduction of the Precautionary Action
Zone (PAZ) and strengthening of the risk
management system will be undertaken.
In recognition that it is our
responsibility to provide the international
community with accurate information
regarding the accident, we have provided
national governments and international
organizations with accident information
and received various IAEA mission
teams. In particular, we developed and
submitted two reports in June 2011 and in
September 2011 to the IAEA, explaining
the accident sequence identified up to
that time, actions taken to deal with the
Fukushima Dai-ichi accident and those
affected, and lessons learned from the
accident.Sincethen,wehavedisseminated
additional information on the accident on
various occasions including the IAEA
International Experts’ Meeting held in
March 2012. This report explains the
actions taken after the accident and is also
placed as a part of providing information
under the framework of the Convention
on Nuclear Safety. We hope this will
contribute to enhance nuclear safety all
over the world.
We will continuously commit
ourselves to deal with the accident
and proceeding with investigation and
verification of the accident, and will
release additional information and the
results of analysis on the accident to the
world, preparing for “the Fukushima
Ministerial Conference on Nuclear
Safety” scheduled for December 2012 in
Japan.
The major factor that aggravated the
accident is that the people involved in
nuclear power generation in Japan had not
seriously addressed the latest knowledge
about tsunami and international standards
and best practices for nuclear safety
including severe accident measures, and
adequate preparation has not beenmade in
the aspects of the systems, organizations,
human resources, equipment and
operation. We will definitely correct these
flaws through the actions mentioned
above. In addition, people in all levels
involved in nuclear power generation
will maintain and improve their technical
skills, while maintaining close relations
with the international community, and
continue to review and enhance nuclear
safety to regain trust at home and abroad.
More than one year has passed
since the Fukushima Dai-ichi accident
occurred. This accident is a very severe
one as shown by the facts: electrical
systems lost their functions extensively
due to the common external event of the
earthquake and tsunami; severe accidents
of fuel damage and core melts occurred
simultaneously at multiple units; the
accident affected a large area around the
site; and more than 100,000 people are
still leading painful lives as evacuees.
The on-site situation is also quite
severe. We internationally have no
experience in accurately understanding
the state inside the severely damaged
reactors, taking out damaged fuel
from such reactors and taking steps for
decommissioning, and it is supposed that
it will take several decades to accomplish
such work. It is also viewed that new
technologies will be required for such
works. Besides, many challenges remain
in improving the reliability of measures,
such as the presence of a large amount of
waste and contaminated water, and the
fact that many pieces of the equipment for
circulation injection cooling system are
temporally construction. In addressing
these challenges, it is necessary for us
to gather international knowledge and
utilize it.
There are a number of nuclear
facilities in Japan and it is necessary to
ensure their safety. Looking back on
the accident, although the Fukushima
Dai-ichi accident was caused directly
by natural disasters, i.e. an earthquake
and a tsunami, the assumption of these
hazards had been insufficient, and
preparations for response to a complex
disaster of natural hazards and an
accident at a nuclear power station had
been not enough either. So far, provisions
for a severe accident have been left to
operators’ voluntary arrangements, and
have not been a regulatory requirement.
Japan must reflect on these points. In the
new regulatory system, measures related
to the above-described preparations are
included in the regulatory requirements.
We must take it seriously that insufficient
safety measures taken so far aggravated
the accident. Concerning the regulatory
system and activities, continuous
improvements have to be made, taking
new technical knowledge into account. At
the same time, operators have to establish
a “safety culture” in which safety levels
are ceaselessly reviewed. In the process,
it is necessary to actively keep up with
the best practices in the world by having
close interactions with the international
community and working closely with
them. Japan is determined to surely
establish a new organization/structure
which will be able to respond to any
emergency properly.
This report describes how Japan has
responded to and what lessons Japan
learned from the accident, and what ac-
tions Japan will take in the future, from
the aspects of external events, design,
severe accident management, domes-
tic organizations, emergency response
and international cooperation. Although
it will take still long time to clarify the
entirety of all aspects of the accident and
identify lessons-learned, we will continu-
ously share new knowledge and lessons
with the international community at vari-
ous occasions, such as, under the Con-
vention on Nuclear Safety or the IAEA
framework, and contribute to enhance-
ment of nuclear safety in the world. We
are also committed to dedicating all our
efforts to make the best use of global cut-
ting edge knowledge and technologies
in response to accidents in the future.
