Results of the International Symposium on Seismic Safety of Nuclear Power Plans and Lessons Learned from the Niigataken Chuetsu‑oki Earthquake－ Post‑quake status of the Kashiwazaki‑
Kariwa Nuclear Power Station (Report #14) －March 5, 2008 rev1
Japan Nuclear Technology Institute
２．Application / participation status
１．Outlines of the symposium（１）Date：February 26 (Tue) – 27 (Wed), 2008
（２）Venue：Culture Hall, Kashiwazaki Sangyo Bunka Kaikan (Kashiwazaki City, Niigata Prefecture)（３）Organizers：Japan Atomic Industrial Forum
Japan Nuclear Technology InstituteCentral Research Institute of Electric Power Industry（４）Sponsors：
Nuclear Safety Research Association, Japanese Geotechnical Society, Japan Society of Civil
Engineering, Japan Society of Mechanical Engineers, Architectural Institute of Japan, Atomic Energy
Society of Japan, Japan Atomic Energy Relations Organization, Japan Association for Earthquake
Engineering, Japan Electric Association, American Society of Mechanical Engineers (ASME), Nuclear
Energy Institute (NEI, U.S.), Electric Power Research Institute (EPRI, U.S.)（５）Purport:
・ To gather engineering insights from around the world to help the industry design, build and manage
safer nuclear power plants in the future, in view of the impact of the Niigataken Chuetsu‑
oki
Earthquake on the Kashiwazaki‑
Kariwa Nuclear Power Station
・ To gather Japanese and overseas experts in the local community of the Kashiwazaki‑
Kariwa NPS,
and organize an international symposium, as titled above, with participation of the general public（６）Program
ａ．Opening address, welcome address, keynote address and special lectureｂ．Session 1 <Integrity Evaluation of Equipment Affected by the Earthquake>・Introducing Japanese and overseas methods for assessing the integrity of plant equipment affectedby earthquakes
・Exchanging opinions about the assessment carried out at the Kashiwazaki‑
Kariwa NPS, which wasaffected by the Niigata‑
ken Chuetsu‑
oki Earthquake
ｃ．Session 2 <Earthquake Induced Ground Deformation ‑‑‑Its Impact and Safety Significance>
Introducing and exchanging opinions about the latest Japanese and overseas insights into nuclear
power plants measures against ground deformation, which caused damage to numerous facilities
at the Kashiwazaki‑
Kariwa NPS
ｄ．Session 3 <Emergency Preparedness and Fire Protection>
・Introducing cases of natural disasters that have affected nuclear power stations in Japan andabroad・Exchanging opinions about emergency preparedness and fire protection measures, implemented invarious countries
ｅ．Concluding session and closing（１）The application period was initially scheduled for December 20 to February 15. However, it was cut
short on February 8 after approx. 600 applications were submitted to the planned capacity of 400.
（２）As indicated below, approx. 550 people actually attended the event, reflecting a high level of interest
and expectations for the symposium.
ａ．502 Japanese participants (including the chairperson, 15 panelists, 24 press personnel from 20
companies and 60 residents of Niigata Prefecture)ｂ．47 international participants (including the chairperson and 12 panelists)
Total:549（３）Since the number of participants was greater than originally planned, the Main Hall on the 3rd floorof the same building was set up as a second venue (with video and audio from the main symposium
distributed via monitors).
<Main participating organizations from abroad>
United States：American Society of Mechanical Engineers (ASME), Nuclear Energy Institute (NEI),Electric Power Research Institute (EPRI), Institute of Nuclear Power Operations (INPO),
Pacific Gas & Electric Company (PG&E), Entergy
France：Electricite de France (EDF), Autorite de surete nucleaire (ASN),
Institut de Radioprotection et de Surete Nucleaire (IRSN)
South Korea：Korean Atomic Energy Research Institute (KAERI)
India：Nuclear Power Corporation of India Limited (NPCIL)
South Africa：Pebble Bed Modular Reactor (PTY)International organizations：World Association of Nuclear Operators (WANO), WANO Tokyo Center (WANO‑
TC)

３．Implementation outcome
The outcome of the symposium is outlined in the attachments. The overall highlights are as follows:（１）This symposium was conducted in the intensive 2‑
day schedule. Each panelist provided information
based on facts and experiences. There were active discussions of high quality among panelists andbetween panelists and the audience.
（２）The participants established a common perception that no damage was observed in safety‑
significant
components. Some pointed out that this was because of good practices in Japan, e.g. the applicationof strict design standards and substantial margin allowed for safety.
This indicates that the past safety measures and seismic designs, applied to nuclear power plants
were appropriate. At the same time, the future task remains on the need of a quantitative assessmenton the safety margin.
（３）Some pointed out that damage to non‑safety significant components should not be ignored, even if
they have no safety significance. Attention should be paid to facilities of low quake resilience
so as not to compromise the power station s overall functionality.
（４）Safety‑
significant facilities are built on rock foundation, and were able to fulfill the shutting
down , cooling and containing functions sufficiently in this earthquake. Yet, in view ofthe fact that the Kashiwazaki‑
Kariwa NPS is still undergoing inspections and tests, some pointed to
the need for final assessment on support performance based on the results of the inspections / tests.
（５）Although natural disasters of this magnitude do not occur frequently, some highlighted the importanceof ① establishing an appropriate crisis management organization, ② continually implementing
training and other forms of personnel education, and ③ disseminating information appropriately withplain language.
（６）The nuclear energy industry is a global community, and individual operators must share information
as appropriate. In addition, some raised expectations that relevant information is distributed not
only among plant operators but also to the mass media, public and local governments.
（７）Local Kashiwazaki residents said that convening this international symposium in the local Kashiwazaki
instead of some major city, contributed significantly to providing a sense of relief as well as
safety .
（８）As a whole, many expressed frank appreciation of the sincere exchange of discussions among experts
from various countries. Local media reports were also accurate and in a calm tone.
ENDAttachment

Results of the International Symposium on Seismic Safety of Nuclear Power Plans and Lessons Learned from the Niigataken Chuetsu‑
oki Earthquake
１．Welcome address<Hiroshi Aida, Kashiwazaki City Mayor, Japan>
ａ．The people of Kashiwazaki City live alongside the nuclear power station every day.
While having a sense of pride for cooperating with a national policy, they also feel
major concerns about the safety of the power station every time some incident occurs.
ｂ．This earthquake did not result in a nuclear disaster because basic safety functions
worked as designed. However, the delay in extinguishing the transformer fire and therelease of a minute amount of radioactive substances caused concerns of radiation
contamination not only within the prefecture but also across the nation and abroad.
Local businesses suffered financial damage from negative publicity.
ｃ．According to a survey on local citizens on post‑
quake reconstruction, the largest
ratio of respondents cited safety assurance of the nuclear power station as themost important aspect.
ｄ．Holding this symposium at the local community has a special significance. It is hopedthat the symposium ends fruitfully in fostering a sense of security as well as
safety concerning the presence of the nuclear power station.

<Hiroo Shinada, Kariwa Village Mayor, Japan>
ａ．The Kashiwazaki and Kariwa areas suffered major earthquakes in 2005 and 2007. We
are thankful of the offer of help extended from the rest of Japan and abroad. We wish
to repay the kindness through rebuilding the affected communities fully.
ｂ．This symposium brings together human wisdom. I hope experts will describe informationin the way non‑engineering types like myself can easily understand.
ｃ．There is a Japanese proverb that says,
Flexibility conquers rigidity . Ourcommunities have structures built hundreds of years ago, or even over one thousand
years ago. We did not have a steel‑frame technology then, but skillfully used timbers.
Today, we have hardware solutions to address quake issues. Yet, even with the mostresilient of structures, it is necessary to explore wisdom of adapting to the treatsof nature.
ｄ．I hope this symposium will fully explore human wisdom to achieve fruitful discussions.

２．Keynote address<Tokio Kanoh, Member of the House of Councilors, Japan>

Earthquakes and Nuclear Power Plants

ａ．The shutdown of the Kashiwazaki‑
Kariwa NPS ① affects power supply and demand, ② increase costs and burden on the
management and ③ increases the emission of greenhouse gasses. Nuclear energy has a role of great significance.
ｂ．Meanwhile, safety assurance of nuclear energy is the top priority task. The plant should resume its operation urgently
on the premise of safety assurance. The government shares the same stance.
ｃ．There is a huge gap between safety in the technological context and security in the social context whenit comes to nuclear energy. Media hold the key in either narrowing or widening this gap. Media must recognize theenormous role it is playing.
ｄ．To resolve miscellaneous tasks, it is important to implement the following withwisdom ,courageandconsideration for the future:① Swift information strategy (Swiftly gathering / analyzing information; Sharing information among nuclear energy
businesses, national government, local governments, media and the public; Reinforcing training on after‑hours
emergency information coordination, etc.)② Media response (Handling aerial media coverage by helicopter; Swiftly distributing information on reactor
safety , significant discharge of radioactive substances and necessity for evacuation in the initialreport if possible; Explaining the assessment of the situation in plain terms)③ Education improvement / information provision (school education, on‑site lessons, various symposiums, etc.)
ｅ．Concluding the address by quoting the former New York Mayor Rudolph Giuliani
We, people in nuclear, never give up, never have, and never will.

<Lucas Mampaey, Managing Director, WANO>

Nuclear Safety for Our World s Future

ａ．Nuclear power generation has been considered essential for securing energy security / stable energy supply andoptimizing energy sources. More recently, nuclear energy is attracting international attention as a crucial systemthat provides solutions to global environmental issues.
ｂ．INPO was established after U.S. energy operators learned from the 1979 TMI incident that it is necessary to work
together in pursuing the highest standard, in addition to adopting regulations.
WANO was established after nuclear operators around the world learned from the 1986 Chrynobyl accident that they
have collective responsibility in continuously improving nuclear facilities.
ｃ．The primary responsibility of nuclear safety lies in actual operators of nuclear power stations. They must not
only observe regulations, but also maintain the stance of constantly learning and exploring safety to enhance safety
performance. To this end, information and knowledge must be publicly offered internationally for mutual
collaboration.
ｄ．Social confidence is not something that comes by easily. It can only be attained on the premise of securing advanced
nuclear safety.

３．Special lecture<Ichiro Takekuro, Executive Vice‑
President and Chief Nuclear Officer, TEPCO> Quest for Safety–Enhancing Seismic Safety and E Preparedness in light of the Niigataken Chuetsu‑
oki Earthquake‑ａ．TEPCO had the following basic policies in implementing actions for anti‑
quake safety and disaster prevention:① Thorough investigation of facts, ② Transparent assessment process, ③ Sharing of lessons learned and④ Community‑oriented considerations and progressｂ．Future initiatives are as listed below:① Continuing to evaluate the integrity of equipment through inspections and analyses② Drawing up the new design‑basis earthquake ground motion (Ss) based on the results of the on‑going geologicalsurveys in land and offshore areas③ Conducting anti‑
quake safety assessment of facilities based on the new Ss, and providing reinforcement to themas required④ Steadily reinforcing the crisis management system according to planｃ．Conclusion① We will continue to tap into domestic and overseas knowledge in examining the Kashiwazaki‑
Kariwa NPS. Throughthe process, TEPCO nuclear power stations will have their anti‑
quake safety and disaster prevention properties
reinforced.
② We want to share our experiences and lessons learned in this earthquake with the rest of the world. This way,
all parties can work together to achieve international nuclear safety.
③ I hope that international cooperation will expand to enhance anti‑
quake safety, that international harmonization
will be achieved on the standards of anti‑
quake designs and safety assessment, and that this symposium serves
as the trigger for materializing these visions.

４．Session 1 <Integrity Evaluation of Equipment Affected by the Earthquake>
Introducing Japanese and overseas methods for assessing the integrity of plant equipment affected by<Chairpersons summary>earthquakes, and exchanging opinions about the assessment carried out at the Kashiwazaki‑
Kariwa NPS, which○ Equipment of safety significance suffered almost no damage. This is
was affected by the Niitaga‑
ken Chuetsu‑
ki Earthquakea reflection of good practices in Japan, e.g. application of strict
design standards and substantial safety margin allowed.
Shojiro Matsuura (Advisor of the Nuclear Safety Research Association and former Chairman of the Nuclear Safety
Co‑
chair
○ In conducting integrity assessment following anearthquake of aCommission, Japan)
persons
scale
that
exceeds
thedesign
basis
,
TEPCO
combines
inspections and
J. Robert Sims (Senior Vice President for Codes and Standards, ASME, US)analysis to assesses components of safety significance. If such an① The Evaluation Method for Seismic Design of ASME MechanicalJohn Stevenson, ASME, US
inspection finds an abnormality, or if analysis identifies figures
Distribution Systems and Components
outside the allowable range, an additional inspection is conducted for② Inspection and Analysis of Kashiwazaki‑
Kariwa Nuclear Power Station Kazuhiko Yamashita, TEPCO, Japan
comprehensive assessment. It is important to follow this protocol.
③ EPRI Independent Peer Review of TEPCO Seismic Walkdown and Evaluation
Gregory S Hardy, EPRI, US○ Any damage, even if it is on components of no safety significance, mustof the Kashiwazaki‑
Kariwa Nuclear Plants
not be ignored. Attention should be paid to facilities of low quake
Toshiharu Nomoto, Chairman of the SANE
Presenta ④ Interim report of the Structural Integrity Assessment Committee forresilience so as not to compromise the power station s overall
and Professor Emeritus of thetions
Nuclear Components damaged by Earthquake (SANE)
functionality.
University of Tokyo, Japan○ There is a difference between improving safety technology and⑤ Source of Margins in the Seismic Design of Piping Systems
Pierre Labbe, EDF
improving a sense of relief. It is necessary to explore ways of⑥ Insights from Seismic Risk Analyses of Nuclear Power Plants and their
M.K. Ravindra, member, ASME Standard
enhancing a sense of relief.
relevance to Kashiwazaki‑
Kariwa Nuclear Power Station
Authoring Team, US
Content

５．Session 2 <Earthquake Induced Ground Deformation ‑‑‑Its Impact and Safety Significance>
ContentCo‑
chair
persons

Presenta
tions

Introducing and exchanging opinions about the latest Japanese and overseas<Chairpersons summary>insights into nuclear power plants measures against ground deformation,○ Safety‑significant facilities are built on rock foundation, and were able to fulfill the shutting down ,which caused damage to numerous facilities at the Kashiwazaki‑
Kariwa NPS
cooling and containing functions sufficiently in this earthquake. Yet, in view of the fact thatat the time of the Niigata‑
ken Chuetsu‑
oki Earthquake
the Kashiwazaki‑
Kariwa NPS is still undergoing inspections and tests, it is necessary to conduct final
assessment on support performance based on the results of the inspections / tests.
Takaji Kokusho (Professor, Civil Engineering Department, Science and○ Some general structures, e.g. underground piping for fire fighting use, are laid on backfilled foundation,
Engineering School, Chuo University, Japan)
and suffered damage when the foundation subsided. This aspect needs to be reflected upon as a failure
Gregory S Hardy (Member of EPRI Seismic Team, EPRI, US)to fulfill expected performance.
① Seismic performance evaluation of
Junichi Toma, Central Research○
Civil engineering structures maintained integrity despite receiving seismic motions 2.5 times the design
geotechnical works in nuclear power
Institute of Electric Powerbasis. This is believed to be because substantial margins were allowed in safety rates and analysis
plants in Japan
Industry, Japan
assumptions in the stage of designing (with particularly large margin allowed in civil engineering).
②
Status and Mechanism of Ground
However, this is still the qualitative assessment stage, and a quantitative assessment must be carried
Deformation of Kashiwazaki‑
Kariwa NPS
Toshiaki Sakai, TEPCO, Japanout from now.
by Niigataken Chuetsu‑
oki Earthquake○ The areas around plant buildings suffered tremor‑
induced land subsidence, different from liquefaction,
and were affected significantly by long‑
period ground motions.
③ Countermeasures for Earthquake Induced○ This symposium was limited to civil‑
engineering assessment, but anti‑
quake safety of nuclear power stations
Norman A. Abrahamson, PG&E, US
Ground Deformation at Power Plants
must be examined in a cross‑disciplinary approach covering the fields of geology, civil engineering andmechanical engineering.

６．Session 3 <Emergency Preparedness and Fire Protection>
ContentCo‑
chair
persons

Presenta
tions

Introducing cases of natural disasters that have affected nuclear power stations in Japan andabroad, and exchanging opinions about emergency preparedness and fire protection measures,
implemented in various countries
Takashi Shoji (Secretary General, WANO‑
TC)David Modeen (Director, External Affairs, Nuclear Power Sector, EPRI, US① Emergency Preparedness Plan of Nuclear Power Plants in the
George Felgate, INPO, US
United States② The Measures for Emergency Preparedness and Fire Protection
Laurent Stricker, EDF
at Nuclear Power Plants in France③ The Experience of Emergency Preparedness at Waterford
James Jack Lewis, Entergy, US
Nuclear Power Station④ Countermeasures taken by TEPCOTadayuki Yokomura, TEPCO, Japan<Chairpersons summary>○ Although natural disasters of this magnitude do not occur frequently, it isimportant to ① establish an appropriate crisis management organization, ②
continually implement training and other forms of personnel education, and③ disseminate information appropriately with plain language.
○ TEPCO should make use of knowledge presented by overseas panelists this time toenhance its emergency preparedness and ensure timely dissemination of accurate
information so as to achieve plant administration that gives a sense of security
to local residents.
○ Data on emergency incidents should be gathered on the global scale to actively
make use of overseas information and achieve safe and stable operation of nuclear
power stations.

７．Concluding session
Content
Co‑
Chair
persons

Panelists

Exchanging opinions further on overall debates in Sessions 1 – 3, in exploring
ways of developing safer nuclear power stations in the future.
Michio Ishikawa, President, Japan Nuclear Technology InstituteAlex Marion, Executive Director, Nuclear Operations & Engineering, NEI, US
Shojiro Matsuura
Session 1 Chairperson
Takeji Kokusho
Session 2 Chairperson
David Modeen
Session 3 Chairperson
EDF advisor to the chairman andLaurent Stricker
CEO, Nuclear issue, EDF【Main opinions from the panelists】<Matsuura>ａ．The primary base for sharing knowledge is to establish how to grasp and understand facts.
What comes next is to provide and discuss information openly to share knowledge. Thissymposium is a very good opportunity for this purpose.
ｂ．One of the surest ways to improve communication is to make it a habit to check whether the
information you deliver is received by the intended recipient, and whether the recipient issues
any response.
ｃ．The primary responsibility of nuclear safety lies in actual operators of nuclear power
stations. Instead of becoming complacent, it is more important to constantly aim for higher
levels, constantly examining one s own performance to identify oversight or areas for
improvement. One should even preempt regulatory authorities criticism in improving work
operations. That would be the right thing to do in light of numerous issues raised in this
symposium.
<Kokusho>ａ．The power station should reflect upon the fact that the subsidence of backfilled foundation
led to a fire, and ensure improvement in future construction work. At the same time, it should
be noted that the seismic motions in this earthquake were substantial, had long period andcontained enormous energy. This was one of the lessons learned this time.
ｂ．It is not very effective to suddenly issue some information after the fact. It is mostimportant to establish community relations that put a human face to plant operations, whereby
local residents start to develop a caring and considerate feeling.
ｃ．The frequency of human‑caused disasters is not necessarily lower than the frequency of natural
disasters. Information sharing in this aspect should be also stressed in the symposium.
<D.Modeen>
ａ．We must be conscious about how a fire should be detected, how the initial fire‑fighting
operation should be carried out, and how solid training can be provided.
ｂ．EPRI demands that, if an activity is not fully implemented, the applicable employee mustacknowledge the failure in the Quality Assurance program. The requirement urges workers todisclose such situations voluntarily and handle them by themselves.
ｃ．Attention must be paid to how event description should be given (i.e. in simple and plain
language) to ensure that workers can learn from various real‑life lessons. Providing too muchinformation may overwhelm the recipient.
<L. Stricker>
ａ．When there was a fire at the Le Blayais power station, we issued 18 press releases over theperiod of 6 hours, and people still accused us of not providing enough information. It is
more important to confirm that messages are received, than to simply deliver information.
ｂ．When new information is obtained somewhere in the world, plant operators must incorporate
it and determine whether the plants, currently in operation, have sufficient safety or require
enhancement. Continuous efforts are required every time an event develops. Information must
be shared among the national government, power stations and regulatory authorities.
ｃ．The fact that there was no damage to safety‑
significant components indicate that sufficient
safety margin was allowed. It is important to understand where such margin is set aside, andwhat portion of the margin has been actually used.

【Chairpersons

summary】○

The nuclear energy industry is a global community, and individual operators must share
information as appropriate to distribute lessons learned to other utilities and other plants.
○ It is hoped that operating experiences and other knowledge will be shared across the industry
and among various countries, and also provided to external parties with a vested interest, e.g.
mass media, the public and local governments.
○ No one would dispute the importance of communication. Efforts must be made to constantly
improve it.
○ This symposium should set a positive precedent. When a major event occurs in another country,
they should organize this kind of symposium to share information.
○ This symposium must be the first privately‑organized one for the said purpose. We arecommitted to continuing efforts like this to create a better nuclear power station for future
generations. All participants cooperation is sought.

８．Main opinions from the audience○ In the comparison of actual seismic response spectrum and theoretical analysis, the data for thehorizontal direction is relatively similar, but the data for the vertical direction is not. What
debates are being taken place in regard to this? It is worrying if there is discrepancy in 3D
analysis.
○ The ground foundation shook substantially, whereas operation floors did not. The attenuation
coefficient between the foundation and buildings should be further examined.
○ Wouldn t earthquakes accelerate facility deterioration over time? Immediately after anearthquake, a reactor may be restarted, but could be suffering from the shortening of long‑term.
○ The fact that plant buildings show varying changes, may point to ground movements at underground
fault, etc. The symposium is insufficient without examining such geological aspects.
○ In examining the maintenance of plant safety in the context of natural disasters, what can we
do to improve general response to natural disasters? What can be done to better coordinate various
activities undertaken by relevant organizations?
○ Organizing this symposium in Kashiwazaki has contributed significantly to not only safety
but also a sense of relief . The difference of mentality between the power‑
producing region
and power‑
consuming region adversely affected the feeling of Kashiwazaki and Kariwa citizens.
However, convening this wonderful international symposium in the quake‑affected community ofKashiwazaki wiped away the negative sentiments, and inspired people for the first time to regain
a sense of pride for having the world s largest nuclear power station in the world.
END