Appendix B: Responses to Phase 2 Information
RequestHuman and Organisational Factors Lessons Learnt
Implementing Post-Fukushima Actions

APPENDIX B – PHASE 2 RESPONSES

Table of contents

Canada ...................................................................................................................................................... 9
Lesson Learnt: CA-01 – Emergency Management Centre (EMC) ................................................... 9
Lesson Learnt: CA-02 Emergency Mitigating Equipment (EME) .................................................. 11
Lesson Learnt: CA-03 Incident Management System (IMS) ......................................................... 12
Lesson Learnt: CA-04 Public Alerting Systems .............................................................................. 14
Lesson Learnt: CA-05 Remote Automated Gamma Monitoring System .................................... 15
Lesson Learnt: CA-06 Emergency Satellite Communication System (ESCS) ............................. 17
Lesson Learnt: CA-07 - Unified RASCAL (Radiological Assessment System forConsequence Analyses) Interface (URI) .......................................................................................... 19
Lesson Learnt: CA-08 Web Emergency Operating Centre (WebEOC) .......................................... 20
Czech Republic....................................................................................................................................... 23
Lesson Learnt: CZ-01 – Provision of Mobile Diesel Generators (MDG)........................................ 23
Lesson Learnt: CZ-02 – Enhancement of Communication Equipment ...................................... 25
Lesson Learnt: CZ-03 – New Backup (Diverse) and Alternate (Mobile) Emergency
Response Center ................................................................................................................................ 27
Lesson Learnt: CZ-04 – Improved Procedures for Diverse and Mobile Equipment& Emergency Operating Procedures ............................................................................................... 29
Lesson Learnt: CZ-05 – New Extensive Damage Mitigation Guidelines (EDMG) ....................... 33
France ...................................................................................................................................................... 35
Lesson Learnt: FR– 01 – Implementation of Operations Team Minimum Staffing ................... 35
Japan ....................................................................................................................................................... 37
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.

Mitigation strategies............................................................................................................... 37
Other procedures and guidelines ......................................................................................... 43
Staffing ..................................................................................................................................... 48
Organizational structures, communication, decision making
authority, and safety culture ................................................................................................ 51
Personnel qualifications and training.................................................................................. 56
Plant instrumentation, controls, human-system interfaces, andcommunications equipment ................................................................................................. 57
Portable equipment/tools, protective gear, and work environments ............................... 58
Work planning, technical support, and emergency response facilities .......................... 59
Emergency response plans .................................................................................................... 63
Extended (longer-term) response ......................................................................................... 63

Korea ....................................................................................................................................................... 65
Lesson Learnt: KR-01 – Stress Test .................................................................................................. 65
Lesson Learnt: KR-02 – Preparation for prolonged emergency ................................................... 66
Lesson Learnt: KR-03 – Reinforcing emergency exercise ............................................................. 67
Lesson Learnt: KR-04 – Mobile power generating equipment ..................................................... 69
Lesson Learnt: KR-05 – Emergency plan for emergency at multiple units ................................ 70
Lesson Learnt: KR-06 – Response Form - Seismic alarm in MCR ................................................ 71
Lesson Learnt: KR-07 – Education and Training ............................................................................ 73
Lesson Learnt: KR-08 – SAMG revision ........................................................................................... 74
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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: KR-09 – Low power shutdown SAMG ................................................................... 75
Lesson Learnt: KR-10 – Improving the emergency response facilities ....................................... 76
Lesson Learnt: KR-11 – Assessment of manpower ....................................................................... 78
Lesson Learnt: KR-12 – Development of accident coping strategies .......................................... 79
Lesson Learnt: KR-13 – Accident Management Program ............................................................. 81
Lesson Learnt: KR-14 – Mobile Equipment ..................................................................................... 82
Lesson Learnt: KR-15 – MACST Team ............................................................................................. 85
Spain ....................................................................................................................................................... 87
Lesson Learnt: SP-01 – Verification and Validation for Emergency Situations ......................... 87
Lesson Learnt: SP–02– Communication During Emergencies ..................................................... 89
Lesson Learnt: SP–03 – Magnetic Help Guides for Portable Equipment ..................................... 90
Lesson Learnt: SP–04 – Visual Aids for Identifying Emergency Equipment............................... 92
Lesson Learnt: SP–05 – Training for Emergency Equipment Transport ..................................... 94
Lesson Learnt: SP–06 – Communication System Improvements ................................................ 95
Lesson Learnt: SP-07 – Stress Management Guide and Posters .................................................. 96
Lesson Learnt: SP-08 – Leadership During Emergency Situations ............................................ 100
Lesson Learnt: SP-09 – Command and Control in Emergencies Guide .................................... 101
United States........................................................................................................................................ 105
Lesson Learnt: US-01 – Human Reliability Analysis Methods for Use of FLEX Strategies
and Equipment ................................................................................................................................ 105
Lesson Learnt: US-02 – FLEX Diesel Generator Experience ........................................................ 106

4

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APPENDIX B – PHASE 2 RESPONSES

On-siteOff-site

Table 1. Lesson Learnt Applicability to Off-site and On-Site Activities

CA-01 - Emergency Management Center (EMC)
CA-02 - Emergency Mitigating Equipment (EME)
CA-03 - Incident Management System (ISM)
CA-04 - Public Alerting Systems
CA-05 - Remote Automated Gamma Monitoring System
CA-06 - Emergency Satellite Communication System (ESCS)
CA-07 - Unified RASCAL (Radiological Assessment System for Consequence Analyses) Interface (URI)
CA-08 - Web Emergency Operating Centre (WebEOC)
CZ-01 - Provision of Mobile Diesel Generators (MDG)
CZ-02 - Enhancement of Communication Equipment
CZ-03 - New Backup (Diverse) and Alternate (Mobile) Emergency Response Center
CZ-04 - Improved Procedures for Diverse and Mobile Equipment & Emergency Operating Procedures
CZ-05 - New Extensive Damage Mitigation Guidelines (EDMG)
FR- 01 - Implementation of Operations Team Minimum Staffing
KR-01 - Stress Test
KR-02 - Preparation for prolonged emergency
KR-03 - Reinforcing emergency exercise
KR-04 - Mobile power generating equipment
KR-05 - Emergency plan for emergency at multiple units
KR-06 - Response Form - Seismic alarm in MCR
KR-07 - Education and Training
KR-08 - SAMG revision
KR-09 - Low power shutdown SAMG
KR-10 - Improving the emergency response facilities
KR-11 - Assessment of manpower
KR-12 - Development of accident coping strategies
KR-13 - Accident Management Program
KR-14 - Mobile Equipment
KR-15 - MACST Team
SP-01 - Verification and Validation for Emergency Situations
SP-07 - Stress Management Guide and Posters
SP-08 - Leadership During Emergency Situations
SP-09 - Command and Control in Emergencies Guide
SP-02- Communication During Emergencies
SP-03 - Magnetic Help Guides for Portable Equipment
SP-04 - Visual Aids for Identifying Emergency Equipment
SP-05 - Training for Emergency Equipment Transport
SP-06 - Communication System Improvements
US-01 - Development and Application of HRA Methods for Use of FLEX Strategies and Equipment
US-02 - FLEX Diesel Generator Experience
Grand Total

16

38

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APPENDIX B – PHASE 2 RESPONSES

Main Control Room

Tech. Support Center

Remote Shut Down

EOF

Other Local Control[other]Table 2. Lesson Learnt Applicability to Plant Location

21

23

4

29

20

2

CA-01 - Emergency Management Center (EMC)
CA-02 - Emergency Mitigating Equipment (EME)
CA-03 - Incident Management System (ISM)
CA-04 - Public Alerting Systems
CA-05 - Remote Automated Gamma Monitoring System
CA-06 - Emergency Satellite Communication System (ESCS)
CA-07 - Unified RASCAL (Radiological Assessment System for Consequence Analyses) Interface (URI)
CA-08 - Web Emergency Operating Centre (WebEOC)
CZ-01 - Provision of Mobile Diesel Generators (MDG)
CZ-02 - Enhancement of Communication Equipment
CZ-03 - New Backup (Diverse) and Alternate (Mobile) Emergency Response Center
CZ-04 - Improved Procedures for Diverse and Mobile Equipment & Emergency Operating Procedures
CZ-05 - New Extensive Damage Mitigation Guidelines (EDMG)
FR- 01 - Implementation of Operations Team Minimum Staffing
KR-01 - Stress Test
KR-02 - Preparation for prolonged emergency
KR-03 - Reinforcing emergency exercise
KR-04 - Mobile power generating equipment
KR-05 - Emergency plan for emergency at multiple units
KR-06 - Response Form - Seismic alarm in MCR
KR-07 - Education and Training
KR-08 - SAMG revision
KR-09 - Low power shutdown SAMG
KR-10 - Improving the emergency response facilities
KR-11 - Assessment of manpower
KR-12 - Development of accident coping strategies
KR-13 - Accident Management Program
KR-14 - Mobile Equipment
KR-15 - MACST Team
SP-01 - Verification and Validation for Emergency Situations
SP-07 - Stress Management Guide and Posters
SP-08 - Leadership During Emergency Situations
SP-09 - Command and Control in Emergencies Guide
SP-02- Communication During Emergencies
SP-03 - Magnetic Help Guides for Portable Equipment
SP-04 - Visual Aids for Identifying Emergency Equipment
SP-05 - Training for Emergency Equipment Transport
SP-06 - Communication System Improvements
US-01 - Development and Application of HRA Methods for Use of FLEX Strategies and Equipment
US-02 - FLEX Diesel Generator Experience
Grand Total

6

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APPENDIX B – PHASE 2 RESPONSES[other]HP-RP Chemist

Security

Maint. Techs

Other ERO

Field Ops.

EOF

MCR Ops.

Table 3. Lesson Learnt Applicability to Job Category

CA-01 - Emergency Management Center (EMC)
CA-02 - Emergency Mitigating Equipment (EME)
CA-03 - Incident Management System (ISM)
CA-04 - Public Alerting Systems
CA-05 - Remote Automated Gamma Monitoring System
CA-06 - Emergency Satellite Communication System (ESCS)
CA-07 - Unified RASCAL Interface
CA-08 - Web Emergency Operating Centre (WebEOC)
CZ-01 - Provision of Mobile Diesel Generators (MDG)
CZ-02 - Enhancement of Communication Equipment
CZ-03 – Diverse and Mobile Emergency Response Center
CZ-04 - Improved Procedures for Diverse and Mobile Equipment & EOPs
CZ-05 - New Extensive Damage Mitigation Guidelines (EDMG)
FR-01 - Implementation of Operations Team Minimum Staffing
KR-01 - Stress Test
KR-02 - Preparation for prolonged emergency
KR-03 - Reinforcing emergency exercise
KR-04 - Mobile power generating equipment
KR-05 - Emergency plan for emergency at multiple units
KR-06 - Response Form - Seismic alarm in MCR
KR-07 - Education and Training
KR-08 - SAMG revision
KR-09 - Low power shutdown SAMG
KR-10 - Improving the emergency response facilities
KR-11 - Assessment of manpower
KR-12 - Development of accident coping strategies
KR-13 - Accident Management Program
KR-14 - Mobile Equipment
KR-15 - MACST Team
SP-01 - Verification and Validation for Emergency Situations
SP-07 - Stress Management Guide and Posters
SP-08 - Leadership During Emergency Situations
SP-09 - Command and Control in Emergencies Guide
SP-02- Communication During Emergencies
SP-03 - Magnetic Help Guides for Portable Equipment
SP-04 - Visual Aids for Identifying Emergency Equipment
SP-05 - Training for Emergency Equipment Transport
SP-06 - Communication System Improvements
US-01 - HRA for Use of FLEX Strategies and Equipment
US-02 - FLEX Diesel Generator Experience
Grand Total

26

23

21

30

11

8

6

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7

APPENDIX B – PHASE 2 RESPONSES

CanadaLesson Learnt: CA-01 – Emergency Management Centre (EMC)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
In light of the lessons learned from the seismic incident at the Fukushima Daiichi Nuclear Power
Plant a Canadian nuclear power plant decided to build on its already substantial emergency
response and control structure to better respond to emergencies, especially those as a result of
natural disasters. As a result the utility decided to merge its Site Management Center (SMC) andthe Corporate Emergency Support Center (CESC) into a new state-of-the art Emergency
Management Center (EMC) facility.
The new EMC is located approximately 1 km from the site and its primary purpose is toprovide emergency response support to the stations. This includes communication withexternal agencies and additional support or resources, such that the stations are able to focus
solely on plant response.
The EMC maintains a VSAT satellite uplink for phone, fax, and Internet, as well as radio,
servers for software operation, electronic dosimetry, external broadcast capability and back-up
power to support sustained operations during infrastructure outages. It is set up to maximize
communications both within the EMC and with off-site resources.
In addition to the EMC, two alternate command posts were established to provide
redundancy should the primary EMC become uninhabitable. The alternate command posts will
also be used as evacuation centres for the purpose of staging response resources when dealing
with a significant all-hazards event that requires longer-term management and on-goingsupport to relieve on-site responders and station operations.
The nuclear power plant also put in place a mobile EMC to back up the EMC or theEmergency Operations Center (EOC), or to augment command requirements depending on thesituation. The mobile EMC is also equipped with back-up power, VSAT capability, and phone,
fax and radio capabilities.
Another nuclear power plant approach was to develop a new off-site Emergency Operations
Center which is located 23KM from site. This facility serves as the center for all off-site actions
during an event and has permanent back-up facilities for each of the on-site Emergency
Facilities in the event these locations are no longer habitable.
Another nuclear power plant is reviewing this approach and is in the early stages of looking
at consolidating ERO facilities.
Supplemental Files: None
Anticipated Benefits: The EMC coordinates and manages the overall Corporate response to anuclear emergency and is EMC is the facility that provides the primary contact forcommunications with the Provincial, regional, and local municipal government centres. It also
provides support with the appropriate technical and financial resources, including the support
to and oversight of the Main Control Room and Station Emergency Operations Centres.
To test the proof of concept of a central command post which amalgamated the existing
SMC and CESC as well as our ability to response to an "all hazards" event, including radiological,
the nuclear power plant participated in an exercise lead by Emergency Management Ontario
which involved more than 50 participating organizations.
During the exercise the EMC successfully served as the central command and logistic control
and coordination point.
The events described in this lesson learnt occurred: Canada from April 2011 to September 201210

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: CA-02 Emergency Mitigating Equipment (EME)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
A major lesson learned from the Fukushima Daiichi nuclear event concerns preparedness forloss of core cooling events due to complete loss of on-site and off-site electrical power. To
address these types of events, which can be initiated by internal or external hazards, Canadian
nuclear power plants have added an additional layer of emergency backup water and electrical
power based on portable emergency mitigating equipment (EME). The EME strategy is designed
to prevent a beyond design basis accident (BDBA) from progressing to a severe accident.

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APPENDIX B – PHASE 2 RESPONSES

In parallel, emergency mitigating equipment guidelines (EMEGs) were developed to provide
instructions on the operation of EME. The inability to predict actual plant conditions that require
the use of EME makes it impossible to provide specific procedural guidance. As such, the EMEGs
provide guidance that can be employed for a variety of conditions. Control room staff willtransfer from emergency operating procedures (EOP) to the EMEGs upon determination that theloss of heat sink event is due to an extended loss of AC power (ELAP).
Should EME not be deployed in a timely manner or otherwise fail to prevent Severe AccidentManagement Guidelines (SAMG) entry conditions from being met, the SAMGs may be entereddirectly from the EMEGs. Under these circumstances, EME may still be available to SAMG for use
in mitigation strategies.
Supplemental Files: None
Anticipated Benefits: The safety benefit is the provision of an additional layer of defense
whereby the Level 4 from the IAEA defense in depth levels is further subdivided into Level 4aand 4b. Level 4a was introduced as an additional layer of defense with the intent of using
additional safety features to provide additional means for preventing a beyond design basis
accident, i.e. with limited or no core melt, from progressing to a severe accident.
The EME strategy helps in reducing the risk from some contributors in plant-specificprobabilistic safety assessments (PSA) (e.g. station blackout and loss of ultimate heat sinkscenarios). EME validation studies indicate that the actions and responses are highly feasible
and warrant consideration to reduce the site risk profile when the actions are directed.
The events described in this lesson learnt occurred: Canada from April 2012 to present

Lesson Learnt: CA-03 Incident Management System (IMS)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories

12

Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
Following the Fukushima event, one Canadian nuclear power plant undertook a review of theorganization's emergency response structure. As a result of this review and additional lessons
learned from the Fukushima event, the nuclear power plant decided to transition to the IncidentManagement System (IMS) in an "All Hazards" approach to emergency response at the station site.
The IMS is an internationally recommended standardized approach to emergency
management, recommended for managing all incidents. It guides how personnel, facilities,
equipment, procedures, and communications may be coordinated during an incident. The IMS
was adopted by the province of Ontario and provides standardized organizational structures,functions, processes and terminology for use at all levels of emergency response in Ontario.
The existing nuclear power plants’ Emergency Plan was reviewed and amended inaccordance with themove to IMS and an all hazards approach to emergency response and a revised Emergency
Response Organisation (ERO) and procedures were produced and included the implementationof an additional 3 shifts to staff the ERO.
In another utility, the formal Incident Command Structure (ICS) is utilized under an AllHazards approach. The ICS model allows integration between all response partners and ensurescommon terminology.
Another utility has adopted IMS in the corporate response structure, and is looking at
extending to the Nuclear Emergency Response Organization
Supplemental Files: None
Anticipated Benefits: Proof of concept exercises were completed at the nuclear power plant as
part of the IMS implementation. ERO personnel viewed the IMS an all hazards approach to
emergency management as a significant improvement over the existing recovery model. The
personnel found that IMS provided an efficient, flexible and consistent structure to manage
events at all levels, allow incidents to be managed in a cohesive manner, facilitating the
response to incidents and cooperation between multiple organizations and jurisdictions.
The IMS establishes a clear line of reporting and authorities within the nuclear power plantorganization for both radiological and "all hazards" events.
The events described in this lesson learnt occurred: Canada from April 2011 to April 2013

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: CA-04 Public Alerting Systems
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
As part of the one Canadian nuclear power plant’s on-going efforts to enhance emergency
preparedness and maintain efficient and effective communications with its residents in theevent of any type of emergency, the nuclear power plant collaborated with radio stations in theregion to implement an Alert FM™ notification. This system utilizes the sub-carrier system of
local FM Radio stations to send a message to a mobile receiver. The receivers sound with an

14

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APPENDIX B – PHASE 2 RESPONSES

auditory warning and a message is broadcast on the screen to provide detailed response
instructions within seconds.
The nuclear power plant provided receivers to all staff whose presence on site is required
to meet the utility licensed operational requirements and to support safe operation of the site
per applicable Provincial and Federal Regulatory requirements. The nuclear power plant also
deployed Alert FM™ technology to local municipality (3000 receiver units) to support public alert
efforts, with the capability to send public alert messages within 10 km of the site (primary zone).
The system is connected to the National Public Alerting System (Alert Ready) and receives all
Threat to Life Alerts distributed through that system.
Another nuclear power plant and associated provincial authority EMO utilizes a mass
notification system (Everbridge) this system is used to notify all residents within the 20KM
planning zone from the station and is augmented by the National Public Alerting System (Alert
Ready). In addition to the notification systems, this province utilizes a Warden Service which
consists of actual members supporting 15 zones of the 20 KM planning zones who support doorto-door notifications with provincial agencies during an event.
Another utility has worked with the pilot project for National Public Alerting System, whichis also employed by the local Municipality to notify local residents. Sirens are also employed to
notify residents within the Automatic Action Zone within 3km of stations.
Supplemental Files: None
Anticipated Benefits: Currently, the Municipality around the nuclear power plant relies onsirens and Rapid Notify to alert the public in the 10-kilometer radius of the nuclear power plantof nuclear emergencies. Rapid Notify is a system that sends out messages to residents usingland-line phone technology. The ever-increasing trend of people becoming more reliant on
cellular technology and replacing their land-line phones with cell phones presents an area
where improvements could be made. The Alert FM™ serves as a public notification
enhancement. It will provide Municipal Emergency Officials the ability to broadcast emergency
messages directly to residents, businesses and institutions with an audible alert and text
message within seconds.
The events described in this lesson learnt occurred: Canada from January 2012 to September
2016

Lesson Learnt: CA-05 Remote Automated Gamma Monitoring System
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]

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APPENDIX B – PHASE 2 RESPONSES

Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
The benefits of an enhanced remote radiological monitoring program were evident after the
Fukushima event for modeling purposes, and early detection of plume pathways to assist in
response and recovery effort. Along with remote monitoring capability t real-time data isessential to quickly identify the existence of radiological hazards during a major event. Thisdata also plays a critical role in supporting the decision making process related to employee andpublic safety.
Prior to the events at Fukushima one Canadian nuclear power plant utility relied on manualcollection and analysis of remote monitoring data, which did not cover sufficient area, with
infrastructure that was not robust enough for large scale disasters. In mid-2012, the utility
Emergency Plan Programs initiated several enhancements to its remote monitoring program.
The enhanced monitoring system consists of an automated gamma monitoring system with
monitors in place within site boundaries as well as various locations within the primary zone
(up to 10 km) to monitor radiological releases. The off-site radiological monitoring consists offixed gamma monitors, deployable gamma monitors and air samplers. Real time information isavailable to Emergency Response staff and response organizations such as Health Canada,
Office of the Fire Marshal and Emergency Management and the Canadian Nuclear Safety
Commission (CNSC). Thermoluminescent dosimeters are located inside the site fence andwithin a 10 km radius of the site.
Primary data transmission is via the cellular network, with back-up satellite capability. Datastorage and external data access is provided through a remote off-site third party data storage
network with appropriate cloud security and backup power and storage facilities.

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APPENDIX B – PHASE 2 RESPONSES

Nu-PathNET® (EM), a radiological monitoring database and analytical software application
is utilised to consolidate all remote monitoring data and support emergency event response
functions.
An additional nuclear power plant developed a Radiation Boundary Monitoring System (RBM)
which consists of 16 fixed boundary gamma detectors radially arranged 1KM around the site
proper. These detectors transmit via cellular repeaters directly into the MCR and can be viewed
remotely by all ERO staff. The RBM devices are solar powered with battery back-up.
Another utility uses automated remote monitoring within the site boundary. Manual
monitoring is performed within the remainder of the 10Km Detailed Planning Zone.
Supplemental Files: None
Anticipated Benefits: The enhanced remote monitoring network in conjunction with NuPathNET® (EM) analytical software will provide operational improvements and increased
efficiency to the utility's emergency response processes. Implementation of the remotemonitoring network will reduce personnel exposure in an emergency event, enhance the qualityof monitoring data reported, eliminate opportunities for human error and increase speed of data
the utility is required to disseminate to government entities and the public. The implementationof automated monitoring equipment and associated software allow response times to beextended and staff resources to be used to respond during emergency events.
The events described in this lesson learnt occurred: Canada from April 2011 to September 2012

Lesson Learnt: CA-06 Emergency Satellite Communication System (ESCS)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
In 2017, one Canadian nuclear power plant moved forward with efforts to implement
enhancements to the utility's on-site and off-site emergency communications capabilities toencompass lessons learned from the events at Fukushima Daiichi and Daiini in 2011. A fixedsite satellite communications system was selected to fulfill this purpose referred to as theEmergency Satellite Communication System (ESCS).
The ESCS provides independent backup capabilities for on-site and off-site communication
during station blackout (SBO) and other beyond design basis accidents (BDBA) in support of thenuclear power plant Nuclear Emergency Response Plan
At each required location, ESCS provides data and voice communication capability throughthe use of fixed-site satellite phones and deployable/fixed VSAT (Very Small Aperture
Terminal) dishes. ESCS acts as one of three methods of emergency communication and provides
multiple phone hubs and Internet connectivity to emergency cloud applications for station
Emergency Operations Centers (EOC).
Another nuclear power plant has adopted the approach of utilizing fixed satellite systems
in the MCR, Security and Off-site Emergency Operations Centers. All other on-site facilities havesatellite phones which provide mobile coverage.
Another utility uses portable satellite phones as backup communications method in themain control rooms, Site Management Centres, Corporate Emergency Operations Facilities andCrisis Management and Communication Centre.
This utility has also implemented capability to restore site communication in a BDBE withextended loss of AC Power, but the systems are portable. This system provides a range offunctionality: Satellite, radio and 4G data.
Supplemental Files: None
Anticipated Benefits: VSAT technology uses satellite connectivity to support multiple phone hubs
and Internet connectivity in both a stationary and mobile setting, allowing for versatility and easein maintaining uninterrupted connectivity. This approach will allow for continued, uninterrupted
information and data transmission to off-site and mobile Emergency Command Centers (EMC)and external agencies in the event of primary communications infrastructure challenges during
large-scale events when plant systems and environments could be challenged.

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APPENDIX B – PHASE 2 RESPONSESThe events described in this lesson learnt occurred: Canada from April 2011 to April 2017

Lesson Learnt: CA-07 - Unified RASCAL (Radiological Assessment System forConsequence Analyses) Interface (URI)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
Prior to 2015 the software used by utilities and Province of Ontario (Office of the Fire Marshal
and Emergency Management) to calculate off-site radiological conditions and inform protective
actions as defined in the Provincial Nuclear Emergency Response Plant (PNERP) was designed toaddress design basis accidents (DBA) and single-unit accidents. The software had limited
capabilities for beyond design basis accidents (BDBA) and multi-unit events.
Lessons learned from the Fukushima Daiichi Nuclear Power Plant demonstrated the needto provide dose projection capabilities for multi-unit events. In order to enhance the approachto plume dispersion modelling during BDBAs and multi-unit events, the nuclear power plantutilities in Ontario selected the Unified RASCAL Interface (URI) to replace the previous dose
projection tool. The URI tool was developed in the United States through a partnership ofEntergy and Exelon. The interface provides site-specific overlay of meteorological, dispersion,and dose assessment models.
Supplemental Files: None
Anticipated Benefits: The Unified RASCAL Interface (URI) tool will be used to project doses andsupport decisions to implement or not implement protective measures of the public after anuclear event as defined by the Provincial Nuclear Emergency Response Plan. It will provide
site-specific overlay of meteorological, dispersion, and dose assessment models and provide
multi-unit dose assessment capability allowing the summing of up to five separate releases
from separate release points. The tool will allow for source term back calculation, allowing
operators to adjust model projections even with limited in-plant data.
The events described in this lesson learnt occurred: Canada from April 2011 to September 2012

Lesson Learnt: CA-08 Web Emergency Operating Centre (WebEOC)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories

20

Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description
Canadian nuclear power plants’ review of post Fukushima lessons learned indicated a need toenhance the organizations ability to effectively communicate information with external
agencies, most importantly Ontario's Office of the Fire Marshal and Emergency Management(OFMEM) and Canadian Nuclear Safety Commission (CNSC), during a broader scope of extreme
events than had previously been considered. It was determined the following informationneeded to be included:•

General situation and plant status.

•

Necessary unit specific information for units in an emergency state.

•

Location and magnitude of any off-site releases should they occur.

In 2012, the nuclear power plants implemented WebEOC, an emergency management
software application, as the primary means to effectively manage an emergency response to
any or all hazards. The application is used by all Emergency Response Organization Command
staff to ensure interoperability and management of strategic objectives, strategies, and tactics.
The application also provides a forum for situational awareness through sharing of emergency
response information internally between command centers on-site as well as with specificexternal stakeholders. This system is operated within the nuclear power plant’s Emergency
Management Center (EMC), which maintains back-up power and communications capabilities
at all times to ensure sustained operation when local infrastructure is challenged.
Supplemental Files: None
Anticipated Benefits: During an Exercise at nuclear power plants, WebEOC proved highly
effective at allowing information entered at the source to be effectively and easily shared withmultiple agencies through Internet access.
The events described in this lesson learnt occurred: Canada from April 2011 to September 2012

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APPENDIX B – PHASE 2 RESPONSES

Czech Republic

Lesson Learnt: CZ-01 – Provision of Mobile Diesel Generators (MDG)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry

Fire brigade, DELTA teamTime / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description
In case of loss of power supply for 6 kV bus bars of emergency power supply (BV, BW, BX)
supplied also from reserve diesel generators - DGs (QV, QW, QX) or emergency station blackout
SBO DGs (0QZ, 7QZ) it is necessary to recover power supply for required consumers (valves,
Instrumentation and Control (I&C) measurement, Post Accident Monitoring System - PAMS). For
this reason, mobile diesel generators KOHLER SDMO were purchased as the last option for power
supply of the most important systems and components. Parameters of the mobile DG (MDG) are
the following: type D440 SILENT, power 440 kVA / 352 kW STBY, Voltage 3x400 V AC and rated
frequency 50 Hz.

Mobile DG 4 x 352 kW (one per unit), voltage 3x400 V AC

The primal goal of the MDG is power supply for I&C systems. 1 MDG per each unit is available
at both Czech power plants (Dukovany, Temelin). When needed, the mobile DGs are transported
by fire brigade to location of operation (together with cable car), cables are emplaced by DELTA
team (Special emergency team dedicated for local actions) between the MDG and bus bars andusing these cables MDG is connected to the relevant bus bars by inspection electrician andoperational electricians. As a support for nuclear power plant personnel, detailed procedures
describing the process of transport, preparation and connection of MDG were developed.
Contribution of the modification to nuclear power plant safety was confirmed byprobabilistic safety assessment (PSA) analysis and feasibility of the required actions was proved
during regular training.
Supplemental Files: https://www.energygeneratorsales.co.uk/sdmo-generator-sales/productdetail/sdmo-d440-440kva352kw-three-phase-industrial-silent-diesel
Anticipated Benefits: Installation of mobile DGs is one of many provisions implemented as apart of post-Fukushima national action plan. Implementation of this modification contributes
to increased redundancy and diversity to ensure the key safety functions. Mobile devices may
be considered as another level of defense in depth.
The events described in this lesson learnt occurred: Czech Republic, 2014 - 2019
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: CZ-02 – Enhancement of Communication Equipment
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description
The challenge was to ensure communication between emergency services inside and outside
Czech nuclear power plants (Dukovany and Temelin) in case of damage of standard
telecommunication infrastructure (e.g. seismic event followed by station blackout).
The possible problem with communication inside the nuclear power plant was solved bypurchasing field phones and radio stations including necessary infrastructure. For using fieldphones, it was necessary to install telephone switchboard inside the shelters located at Czech

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APPENDIX B – PHASE 2 RESPONSES

nuclear power plants (Dukovany and Temelin), to prepare cable lines inside buildings and to
install connection points. Furthermore, antenna systems (together with necessary cables) were
installed as a part of radio stations.
Communication outside the nuclear power plant was solved by purchasing satellite phones
and installation of GSM (Global System for Mobile Communications) repeater in the nuclear
power plant’s shelters including installation of antenna system. Furthermore, backup charging
devices dedicated to charging of satellite phones and radio stations were provided in the
shelters as well.
Functionality and contribution of the new devices was proved during regular emergency
trainings.

Field phones

Radio stations

Antenna systems

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APPENDIX B – PHASE 2 RESPONSES

Satellite phones

Charging devices and transmitters

Supplemental Files: None
Anticipated Benefits: Installation of alternative communication means is one of many
provisions implemented as a part of post-Fukushima national action plan. Implementation ofthis modification is in agreement with emergency preparedness conception to enable
cooperation and communication between all emergency services taken part in emergency
management in case of damage of standard telecommunication infrastructure.
The events described in this lesson learnt occurred: Czech Republic, 2012 - 2013
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: CZ-03 – New Backup (Diverse) and Alternate (Mobile) Emergency
Response Center
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry

Technical Support Center personnel

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description
Backup (diverse) and alternate (mobile) emergency response center were established at nuclear
power plants in the Czech Republic. The aim, based on the National Action Plan - item 59, wasto ensure the functionality of the emergency response organization components even in thecase that the „design” ECC (emergency control center at the nuclear power plant) is unavailable
or for the members of emergency response organization there is not possible to get onto thesite. The aim is to provide an alternative way of managing extraordinary events in case of lossof design basic emergency control center, control center of physical protection and control
center of fire protection). At the same time, it is a solution for concealing shift staff and firebrigade personnel and their equipment in case of unavailability of covers, respectively firebrigade buildings, i.e. in site isolation mode for 72 hours.
The backup (diverse) control center of Emergency Response Organization for Temelín
Nuclear Power Plant (in 2014) and Dukovany Nuclear Power Plant (in2015) were established inneighboring towns in the buildings in which the dosimetry situation in the nuclear power plant
emergency planning zone is monitored.
In case that the both Emergency Response Centers - ERCs (basic and backup) are notavailable or not excessive from any reason, there is necessary to ensure the full functioning of
the Emergency Response Organization (in the event of significant site destruction, when there
is bad radiation situation etc.). To perform this task, three inflatable tents with accessories werepurchased at Temelín and Dukovany Nuclear Power Plant (including generator, air-conditioning,heating, lighting, fuel supply, protective equipment, radiation protection, satellite phone, foodand drink, etc.) This kind of tent is regularly used by army or integrated rescue forces during big
disasters (fire, flooding, earthquake, etc.) in the Czech Republic. The air-inflated hall can belayout on proper place with respect the current radiation situation and meteorologicalconditions. Each tent is stored on a trailer, which can be transported by emergency responseorganization car or other vehicle to a designated location.
Each tent is equipped with a step by step manual so that the construction and installationof accessories can handle even by the no specialist persons.

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APPENDIX B – PHASE 2 RESPONSES

Diverse Emergency Control Center(located in Moravsky Krumlov)

Alternative (Mobile) Emergency Control
CenterBox Truck – (for transporting a tent)

Supplemental Files: None
Anticipated Benefits: Possibility to provide accident management and emergency response
activities when the design bases emergency response center at the site is not available from any
reason.
The events described in this lesson learnt occurred: Czech Republic, 2014 - 2017
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: CZ-04 – Improved Procedures for Diverse and Mobile Equipment &Emergency Operating Procedures
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

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APPENDIX B – PHASE 2 RESPONSES

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry

Fire brigade, DELTA team, TSC members

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description
One of the measures implemented at Czech nuclear power plants after the Fukushima Nuclear
Power Plant accident was installation of Diverse and Mobile (DAM) equipment, which isintended to ensure basic safety functions, especially for long-term blackout events, also called
Extended Loss of AC Power (ELAP) events, complete Loss of Ultimate Heat Sink (LUHS) events,
combination of ELAP and LUHS, as well as multi-unit events. This new DAM equipment
dramatically improved the ability of the plants to respond to all events leading to ELAP and
LUHS caused by external hazards or other initiators.
Using the new DAM equipment required development of new specific procedures to extend
the applicability of emergency procedures taking into account all states resulting from designbasis accidents and as well as design extension conditions. The new DAM procedures are:30•

DAM-1 Primary system injection•

DAM-3 Injection of feedwater into steam generator•

DAM-5 Initial assessment of nuclear power plant status and dislocation of mobile
equipment*

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APPENDIX B – PHASE 2 RESPONSES•

DAM-6 Emergency makeup of demineralized water tanks•

DAM-7 Loss of key parameters measurement•

DAM-8 Boron makeup into the reactor coolant system•

DAM-10 Hydroaccumulators isolation•

DAM-11 Spent fuel pool makeup•

DAM-12 Containment depressurization•

DAM-13 Switch from mobile equipment to design equipment•

DAM-14 Low pressure primary system injection* Discussed further in the example below
The corresponding links to specific DAM procedures were subsequently incorporated into
the original Emergency Operating Procedures (EOPs / ECA-0.0, Blackout), Shutdown procedures(SD / SD-0, Shutdown blackout) and Severe Accident Management Guidelines (SAMG) to provide
a comprehensive and interconnected structure of the emergency management documentation.
Upgraded documentation to cover the events in the scope of design extension conditions leadto significant safety improvements in the area of accident management program
implementation at Czech nuclear power plants.
Subsequently, a safety analysis of recovery of power supply to required electrical loads using
mobile diesel generators, one MDG per unit, was performed by UJV (Czech Nuclear PowerEngineering Company) using a probabilistic safety assessment (PSA) model. Two variants wereconsidered in the analysis: (1) power supply recovery performed for one unit only and (2) power
supply recovery performed sequentially for all four units (with available time 10 hours in total.
Four different external hazards were considered in the analysis: (1) earthquake, (2) high winds,(3) extreme snowfall, and (4) extremely low temperatures. Expected time windows of specificmanipulations were examined (i.e. measured during regular drill) and discussed with plant
personnel. Task allocation, way of communication, and sequence of required actions werediscussed with the relevant local operators. The following personnel were required to take apart in the scenario:•

Control room operators (3 per unit)•

Shift electrician (1 per nuclear power plant)•

Inspection electrician* (1 per nuclear power plant)•

Operational electrician (4 per nuclear power plant)•

Fire brigade•

DELTA team (Special emergency team dedicated for local actions, 4 per nuclear power
plant)* Discussed further under Recommendation 1, Staffing
UJV developed the following timeline to illustrate the sequence of the expected failures andrequired actions:

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APPENDIX B – PHASE 2 RESPONSES

Failure probability of power supply recovery from MDG was calculated for “normal“ conditions
as well as for cases caused by external events.

Mobile DG 4 x 352 kW (one per unit), voltage 3x400 V AC

Supplemental Files: None
Anticipated Benefits: Upgrade of documentation to cover the events in the scope of design
extension conditions leading to the significant safety improvement in the area of accident
management program implementation at Czech nuclear power plants.
Based on the analyses describe above, two recommendations were formulated:•

Staffing
In the case of a multiunit event, some problems to perform required actions by theinspection electrician in time may be expected, since there is only one inspection
electrician per nuclear power plant. UJV recommended an increase in the number ofinspection electricians or to share some of the responsibilities of this position with shiftelectricians, of which there are four per nuclear power plant.

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APPENDIX B – PHASE 2 RESPONSES•

Procedures
It was found that some of the required actions (e.g. transport of a heavy spool with cablesfrom the ground floor to the second floor) may require increased number of personnel.
It would be beneficial to state such information directly in DAM procedures to avoid any
delays during emergencies.

The events described in this lesson learnt occurred: Czech Republic, 2014-2017
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: CZ-05 – New Extensive Damage Mitigation Guidelines (EDMG)
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry

Fire brigade, DELTA team, TSC members

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description
Verification of flow paths availability and access under SBO conditions were included into socalled “FLEX” approach (use of Diverse and Mobile equipment – “DAM”). Component parts ofthis approach were (1) justification and verification of selected approach and proposed
measures, (2) development of “DAM” support guidelines and procedures and (3) development ofExtensive Damage Mitigation Guidelines (EDMG).
Justification and verification of the capability of the newly implemented measures toperform the required functions, the capability of personnel to perform the required functionsin the required time, and the adequacy of organizational measures were developed by assessing
compliance with the following criteria:•

NEI 12-06, Diverse and Flexible Coping Strategies (FLEX) Implementation Guide•

WENRA Safety reference Levels for Existing Reactors, Issue F – Design extension
Conditions.

With an external supplier the following procedures for use of DAM equipment have beendeveloped in 2015 (FLEX and EDMG procedures):•

Guidelines for the use of DAM equipment (P003y): This guideline describes usage all
mobile and portable equipment depend on unit parameters to recover long term stable
plant status or mitigate emergency plant status – usage of these guidelines wasincorporated to the Emergency Operating Procedures and Severe Accident Management
Guidelines (SAMGs)•

Local manipulation sheets for the use of DAM equipment - (procedures P331 a P334)
include detail description of measures in case of total loos of all means to ensure electric
power (SBO – station blackout) or remove decay heat (LUHS - Loss of Ultimate Heat Sink).

•

Requirements for operability of DAM equipment - (procedure B155j with therequirements for operability of DAM was implemented to ensure availability of DAM
equipment)•

Guidelines for the response to significant damage of the site (EDMG) - (procedure P004y
EDMG describes recovery of the plant in case of severe damage of plant infrastructure)
There are described most important actions to keep nuclear safety, such as confirm
reactor trip, to ensure core cooling, feeding SG, containment tightness and spent fuelpool cooling. Guideline also solves plant organization, leading and control role, settingof communication, and cooperation with secure services, fire brigade, radiological groupand medicine care with accordance of Emergency Plan.

All these procedures were subject to the standard process of verification within the processof preparation of the documentation. Validation of the selected procedures has been performedby emergency exercises and drills. The procedures are included in regular training of the staffof the Technical Support Center - TSC, team of emergency director and operating shift
In addition, CEZ developed a more systematic methodology for identification of non-routine
flow paths for delivery of coolant or providing power in case of severe plant damage. The results
were included into Technical Support Guideline TSG-3, Site Capabilities that was added to SAMG
package in frame of SAMG update in 2018 based on PWR OG project.
Supplemental Files: None
Anticipated Benefits: Upgrade of documentation to cover the events in the scope of design
extension conditions leading to the significant safety improvement in the area of accident
management program implementation at Czech nuclear power plants. New guidelines andupgrade of guidelines and procedures are in accordance with Post Fukushima National Action
plan (based on National Report on Stress Tests of nuclear power plants Dukovany and Temelin,
December 2011), item 53, 56, 59 and 77
The events described in this lesson learnt occurred: Czech Republic, 2014-2018
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

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APPENDIX B – PHASE 2 RESPONSESFranceLesson Learnt: FR– 01 – Implementation of Operations Team Minimum Staffing
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description
The Fukushima accident showed the need to guarantee the autonomy of nuclear power plantstaff, especially after extreme natural hazards when the plant can be isolated (e.g. Blayais in1999 in France as well).
The post-Fukushima regulatory request (ECS35-I) was to ensure that all actions required arefeasible despite extreme context and can be performed by qualified staff.
The nuclear operator developed a method focusing on operations (main control room (MCR)
and field actors) in interface with national crisis teams, using simulator calculations for defining
the timing and deadlines to perform critical actions to prevent loss of control: the goal was toestablish the general time and staffing with sufficient margin to control situation. The nuclear
operator conducted several exercises in 2014, 2015, 2016 on one or two MCR simulators on lossof coolant (LoC) and loss of electricity (LoE) scenarios that were controlled by the operations
team. The nuclear operator assumed that the operation team could have to perform them allwithout support of local emergency teams for 24 hours. It led to adding one supervisor for thetwo operators in MCR by 2020; thus, chief and deputy of operation team are in charge of key
decisions, safety control, and external interfaces.
To reduce the operations staff workload, some prioritization of operation actions should be
introduced by modifying dedicated procedures but the diversity of situations due to unexpectedscenarios limits this possibility. Thus, it is potentially leaving an important workload for theoperations team in real time. The operations team workload has been adapted by changing roles
and responsibilities as proposed by the operator. However, the exercises (mentioned above)
highlighted the challenge of accumulating functions by the lead members of the operations
team (chief, deputy and supervisor).
The exercises also showed also the multitude of influence factors on human actions in field(e.g. darkness) and the difficulty to translate them into quantitative analyses of time andstaffing margins. In this domain, the implementation of post-Fukushima actions revealed that
there is a lack of fundamental scientific and evidence-based data on the quantitative impact ofinfluence factors on human actions performance. The conduct of risk analysis in case of
extreme events may further show that design measures could be necessary to protect paths andworkplaces to ensure that necessary actions could be performed.
Supplemental Files: None
Anticipated Benefits: Validation of staffing and timing margins through the use of realistic
beyond-design-basis simulations will improve understanding of the needs that must be met forsuccessful event mitigation and improve confidence in the operations team’s capability to meetthese demands.
The events described in this lesson learnt occurred: 2014 - 2016
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

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APPENDIX B – PHASE 2 RESPONSESJapan

The Federation of Electric Power Companies (FEPC) responded to the Phase 2 information
request in narrative format as an alternative to the template format seen elsewhere in thisappendix. The following report is the FEPC response to the Phase 2 information request.

1. MITIGATION STRATEGIES (i.e. strategies for maintaining or restoring corecooling, containment, and spent fuel pool cooling capabilities)

Introduction
Until the Fukushima Nuclear Power Plant Accident, Japan’s nuclear power plants had notcredibly assumed the possibility of a severe accident caused by a beyond- design-basis external
event. The Fukushima Nuclear Power Plant Accident made clear that nuclear power plants’ chainof command was unclear, materials and equipment were lacking, and information sharing andcommunication was not swift and reliable in accident response at the time. Based on the lessons
learned from the Accident, operators have been sorting out the important points in emergency
response and improving emergency response capabilities.
The Fukushima Accident has made it clear that a phased approach is effective in accident
response. Specifically, as shown in Diagram 1, resources can be used most effectively if the timesince the occurrence of the accident is separated into three phases and accident response is
implemented appropriately in each phase.
Phase 1 is defined as the time from the occurrence of the accident until 12 hours after theaccident based on the experience gained in the Fukushima Accident. Phase 1 relies on response
only by shift personnel and permanent facilities. This forms the fundamental requirements forsafety facilities.
Phase 2 is defined as the period from 12 hours after the accident to 3 days from theoccurrence of the accident. Staff that were at the station at the time of the accident can be
expected to perform additional accident response measures in this phase. Additional response
may be performed using the mobile equipment installed at the station.
Phase 3 is defined as the period from 3 days after the accident onwards. Offsite support canbe relied upon in this phase.
Based on this phased approach, safety improvement measures from both structural andnonstructural viewpoints, including ERO staffing and manuals, are being discussed.

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APPENDIX B – PHASE 2 RESPONSES

Diagram 1 Conceptual diagram of a phased approach in accident response

The following is an explanation of the equipment that has been strengthened since theAccident.

Core damage prevention measures
The three basic safety functions of commercial reactor facilities are to “stop”, “cool” and“contain”. There are measures in place to prevent significant damage to the core in case of aloss of function of facilities which is to respond to design basis accidents, regardless of cause.
These measures are intended to eliminate unexpected events as a severe accident prevention
measure from a defense in depth perspective.
Assuming a scenario in which the control rod does not operate correctly and emergency
shut down fails despite these measures, there are other measures in place to bring the reactor toa subcritical state (stop) to prevent significant damage to the core.
Examples of measures are as follows.
•

PWR - Install a diversification automatic actuation panel (ATWS mitigation facility) thatwill automatically actuate the auxiliary feedwater pump to inject a boric acid solution.

•

BWR - Suppress reactor output via the recirculation pump trip function that willautomatically stop the reactor coolant recirculation pump (RPT). Control reactivity via
reactor SCRAM using the alternative rod injection function (ARI) independent of thereactor safety protection system and the independent standby liquid control system (SLC)that operates using a different principle from the reactor shutdown function that uses
the control rod.

Regarding the “cooling” function, the highest level of reliability reasonably achievable isrequired for high pressure core spray pumps and other emergency core cooling facilities thatcool the core in an accident. Assuming a scenario in which the emergency core cooling facility
does not actuate and core cooling fails despite these measures, there are other measures in place
to prevent significant damage to the core even when the cooling function of the design basis
accident response facilities of the commercial reactor is lost while the reactor cooling pressure
boundary is at high pressure.
Examples of measures are as follows.
•

38

PWR - Even if all AC power is lost, the turbine-driven auxiliary feedwater pump cancontinue to inject water into the steam generator due to the recently deployed portablestorage battery for the turbine-driven auxiliary oil pump. The primary system can be
depressurized and cooled sufficiently by removing heat from the secondary coolingsystem.

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APPENDIX B – PHASE 2 RESPONSES•BWR - Install a high-pressure alternate injection system. The high-pressure alternate
injection system and the reactor isolation cooling system can be actuated from the field
when the high pressure injection system, which is a design basis accident response
equipment, cannot be actuated due to the function loss of all AC power source and DC
power source system and also the high-pressure alternate injection system cannot be
actuated from the main control room.

There are also measures in place to prevent significant damage to the core when the
depressurization function of the design basis accident response equipment of the commercial
reactor is lost when the reactor cooling pressure boundary is at high pressure.
Examples of response measures are as follows.
•

PWR - Deploy nitrogen cylinders and portable storage batteries. These resources can beused to ensure that the pressurizer relief valve can be actuated at all times so that thereactor coolant boundary depressurizing function can be maintained.

•

BWR - Establish an alternate depressurization logic (alternate automatic depressurization
function) for safety relief valves that will depressurize in response to a different signal than
the automatic depressurization function. Deploy high pressure nitrogen gas cylinders andportable storage batteries to allow actuation of the safety relief valve anytime to maintainthe reactor coolant boundary depressurization function.

There are also measures in place to prevent significant damage to the core even when thecooling function of the design basis accident response equipment of the commercial reactor islost when the reactor coolant pressure boundary is at low pressure.
Examples of response measures are as follows.
•

PWR - The reactor cooling function can be maintained by ensuring the filling pump cancool itself and establishing methods to inject water into the reactor via a mid-sizedpumper truck or pressurized pumper truck.

•

BWR - The reactor cooling function can be maintained by installing a portable lowpressure alternate injection system and a permanent low-pressure alternate injection
system (makeup water pump that does not require cooling of heat generated fromequipment) to respond to scenarios in which there is no time before the core issignificantly damaged.

As seen above, there are various equipment in place to cool the commercial reactor by
reducing the pressure of the reactor coolant pressure boundary from high to low pressure stateeven when the safety functions of the commercial reactor with design basis accident response
equipment are lost.
With regard to the “containment” function, there are equipment such as the containment
vessel spray (equipment to reduce pressure and temperature inside of the containment vessel)
in place in the containment vessel to secure the containment function. Even the equipment likethis has the highest level of reliability that is reasonably achievable. Assuming that thecontainment spray does not function despite these measures, there are other measures in place
to prevent significant damage to the core even when the design basis accident response
equipment’s cooling function of the primary containment vessel is lost.
Examples of response measures are as follows.
•

PWR - The pressure and temperature inside the containment vessel can be reduced byspraying water into the containment vessel from the spray nozzle installed on the upper
part of the vessel using the alternate containment vessel spray pump recently installed
as an alternative to the containment vessel spray pump.

•

BWR - The temperature and pressure inside the primary containment vessel can be
reduced by installing an alternate containment vessel spray cooling system and spraying
water from an external water source into the primary containment vessel.

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APPENDIX B – PHASE 2 RESPONSES

There are measures in place to prevent significant damage to the core by preventing heatfrom accumulating in the core even if the design basis accident response equipment functionof transferring heat to the final heatsink is lost.
Examples of response measures are as follows.
•

PWR - Heat can be transferred to the final heatsink via natural convection cooling in thecontainment vessel by supplying seawater to the containment vessel recirculation unit
through the reactor component cooling system using the recently deployed mid-sizedpumper truck.

•

BWR - Heat can be transferred to the final heatsink by installing the primarycontainment vessel filter vent system which removes the atmospheric gas in the primarycontainment vessel and releases it out into the atmosphere after reducing the levels ofradioactive materials in the gas via the vent filter, and setting the alternate reactor
component cooling system (comprised of the heat exchanger unit and the large capacity
water truck).

The severe accident response equipment used in the measures described above were
designed with different considerations compared to the design basis accident response
equipment. Specifically, the permanent severe accident response equipment were designed sothat their functions would not be lost at the same time as the safety functions for design basis
accident response equipment are lost, aiming to prevent common cause failure. Design
considerations are paid for portable severe accident response equipment, which include storing
equipment in areas that are at least 100 m away from the reactor building so that they are notimpacted by the same event, and deploying at least two sets of equipment, plus another set incase the standby equipment becomes unavailable.

Containment vessel damage prevention measure
There are containment vessel injection equipment and containment vessel cooling measures inplace to reduce the pressure, temperature, radioactive material concentration in thecontainment vessel to prevent containment vessel damage.
Specific examples of countermeasures are shown below.
•

PWR - The permanent alternate low pressure injection pump and portable alternate lowpressure injection pump were recently deployed as a type of containment vessel
injection equipment which sprays water into the containment vessel from thecontainment vessel spray line. Other recently established containment vessel coolingmeasures include passing seawater and coolant through the existing containment vessel
recirculation unit.

•

BWR - An alternate containment vessel spray cooling system (permanent) that uses thecondensate transfer pump and an alternate containment vessel spray cooling system(portable) that uses the portable alternate injection pump to spray water into the primarycontainment vessel from the containment vessel spray header were recently deployed
as containment vessel injection equipment. Measures to cool the primary containment
vessel while maintaining the primary containment vessel boundary through thealternate circulation cooling system via the condensate transfer pump, and measures tocool the primary containment vessel by releasing the primary containment vesselpressure into the atmosphere were recently established as containment vessel coolingmeasures.

In addition to these containment vessel damage prevention measures, difference specificmeasures have been implemented for each of the phenomena that are known to lead tocontainment vessel damage. Specifically, measures have been developed for ① phenomenon inwhich the heat of the molten core corrodes the concrete because the molten core falls into thelower part of containment vessel (molten core concrete interaction (MCCI)), ② phenomenon
where the temperature and pressure rise rapidly as the containment vessel atmosphere isdirectly heated by the molten core as a result of the molten core being released when the

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APPENDIX B – PHASE 2 RESPONSES

containment vessel is at high pressure (direct containment heating (DCH)), ③ phenomenon
where the hot fuel cladding tube and water reacts each other and leads to a hydrogen explosion.
Examples of specific measures are listed below.
① MCCI countermeasures•

PWR - The permanent alternate low pressure injection pump described above can beused to spray water into the containment vessel and cool the molten core as it falls into
the containment vessel, in order to prevent containment vessel damage. Some plants
have separately deployed a pump that can directly inject water into the cavity in thelower part of the reactor. As a result, water can be injected directly into the lower part ofthe containment vessel and the area cooled at an early stage in the event. If the reactor
cooling function is lost and there is significant core damage, water can be injected into
the core using the permanent alternate low pressure injection pump described above todelay or prevent the molten core from falling into the lower part of the containment
vessel.

•BWR - The alternate containment vessel spray cooling system (permanent) or thealternate containment vessel spray cooling system (portable) described above can beused to spray water into the primary containment vessel, cool the molten core that has
fallen into the primary containment vessel, in order to prevent containment vessel
damage. This will allow water to be injected directly into the lower part of the primarycontainment vessel and the area cooled at an early stage in the event. The suppressionof molten core inflow into the dry well sump in addition to the actuation of the lower
primary containment vessel injection equipment should suppress the corrosion of
concrete on the bottom of the sump and prevent contact between the molten core andthe primary containment vessel boundary (steel liner). To this end, a corium shieldcomposed of heat resistant materials was recently installed. Additionally, if the reactor
cooling function is lost and the core sustains significant damage, water will be injected
into the core using the low-pressure alternate injection system (permanent) to delay or
prevent the molten core from falling into the lower part of the primary containment
vessel.

② DCH countermeasures•

PWR - The release of high pressure melt when the reactor pressure vessel is damaged
can be prevented by forcefully depressurizing the primary cooling system through therelease of the existing pressurizer relief valve. In releasing the pressurizer relief valve,
support systems such as the control air are necessary. Even if these support systems are
lost, the opening and closing functions can be recovered by using the recently deployedalternate control air supply equipment.

•

BWR - The release of high pressure melt when the reactor pressure vessel is damaged
can be prevented by rapidly depressurizing the reactor pressure vessel through therelease of the existing pressurizer relief valve. In releasing the safety relief valve, support
systems such as the accumulator for the relief valve full of nitrogen is necessary. Even if
these support systems are lost, the opening and closing functions can be recovered byusing the recently deployed high pressure nitrogen gas cylinders.

③ Hydrogen explosion countermeasures•

PWR - A hydrogen combustion device and a passive autocatalytic recombiner (PAR) wererecently installed. These can reduce hydrogen concentration and prevents a hydrogen
explosion in the containment vessel. To prevent a hydrogen explosion that may impact
the soundness of the annulus even if hydrogen leaks from the containment vessel to theannulus, the hydrogen that has leaked into the annulus will be removed via the existing
annulus air recirculation equipment. To operate the hydrogen exhaust valve in theannulus, support systems such as the control air are necessary. Even if these support
functions are lost, the opening and closing functions can be recovered using the recently
deployed nitrogen cylinders. The hydrogen concentration in the containment vessel can

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APPENDIX B – PHASE 2 RESPONSES

also be measured and monitored using the recently installed portable hydrogenconcentration measuring instrument.
•

BWR - The plant will ensure that the hydrogen and oxygen concentrations will not reachthe combustible range by inactivating the atmosphere inside the primary containment
vessel when starting up the reactor. Measures were put in place to release the air within
the primary containment vessel via the primary containment vessel pressure relief
device if the hydrogen concentration and the oxygen concentration in the primarycontainment vessel rises. A passive autocatalytic recombiner (PAR) was recently
installed in the reactor building to prevent a hydrogen explosion that may impact thesoundness of the reactor building. The hydrogen concentration and oxygen
concentration within the primary containment vessel can be measured and monitored
via the recently installed containment vessel hydrogen concentration meter and theprimary containment vessel oxygen concentration meter.

The severe accident response equipment used in the measures described above were
designed with different considerations compared to the design basis accident response
equipment. Specifically, the permanent severe accident response equipment were designed sothat their functions would not be lost at the same time as the safety functions for design basis
accident response equipment are lost, aiming to prevent common cause failure. Design
considerations are paid for portable severe accident response equipment, which include storing
equipment in areas that are at least 100 m away from the reactor building so that they are notimpacted by the same event, and deploying at least two sets of equipment, plus another set incase the standby equipment becomes unavailable.

Fuel damage prevention measures in the spent fuel storage tank
Equipment to inject water into the spent fuel storage tank and to control the outflow of coolant
are in place to maintain the appropriate water level within the spent fuel storage tank, and tocool the fuel bodies and shield radiation from the fuel bodies. Spent fuel storage tank coolingequipment are in place in preparation for the event that sufficient water levels cannot be
secured for the spent fuel storage tank.
Examples of specific countermeasures are shown below.
•

Common for BWR and PWR
The portable alternate injection system (pumper truck and hose) has been recently
deployed as a spent fuel storage tank injection equipment. The siphon breaker has been
recently deployed as a equipment to control the outflow of coolant from the spent fuelstorage tank. A portable spray system (pumper truck, hose, spray header) has been
recently deployed as a spent fuel storage tank cooling equipment for when sufficientwater levels cannot be secured for the spent fuel storage tank.

Fuel damage prevention measures in a shutdown reactor
Reactor injection equipment have been developed to secure reactor water levels in a shutdown
plant, to maintain cool fuel bodies and shield radiation from the fuel bodies.
Specific examples of countermeasures are as follows.

42•

PWR - Multiple reactor injection measures such as the establishment of the self- coolingof the filling pump and deployment of a mid-sized pumper truck and pressurize pumper
trucks have been recently established.

•

BWR - A portable low pressure alternate injection system has been developed and apermanent low-pressure alternate injection system (a makeup water pump that does not
require cooling itself) has been recently installed to respond to scenarios where there isno time before core damage.

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Equipment to transfer heat to the final heatsink have been recently deployed in preparation
for the loss of design basis accident response equipment function to transfer heat to the finalheat sink.
Examples of specific countermeasures are shown below.
•

PWR - Developed a new method to transfer heat to the final heatsink via containment
vessel natural convection cooling by supplying seawater to the containment vessel
recirculation unit via the reactor component cooling system using the mid-sized pumper
truck that was recently deployed.

•

BWR - Developed a new method to transfer heat to the final heatsink by installing analternate reactor component cooling system (comprised of a heat exchanger unit andlarge capacity water truck).

2. OTHER PROCEDURES AND GUIDELINES (to manage other elements of event or
emergency response not directly supporting the implementation of mitigation
strategies)
1.

Development of procedures related to severe accident response equipmenta.

Ease of switching - Procedures necessary for swift system reconfiguration are to be
developed for equipment that is repurposed as severe accident response equipment insevere accidents. Training is to be conducted to ensure these procedures can be
implemented steadily.

b.

Secure access routes - Effective operation management is to be conducted so that, should asevere accident occur, the roads and passageways in the station can be secured to transport
portable severe accident response equipment or to assess damages done to otherequipment.
Specific examples include:① Secure multiple access routes and their detours to ensure portable severe accident
response equipment can be transported and equipment damage assessed, should a severe
accident occur② Store heavy machinery such as wheel loaders capable of removing obstacles on sitepremises and secure personnel who can operate such heavy machinery

To prepare for the beyond design basis natural disasters in which securing an access route
may prove difficult, multiple access routes including detours are secured; depending on thedamage, the access route that can be recovered earlier will be chosen from the multiple options.
2.

Response related to recovery worka.

Secure spare parts - Appropriate spare parts and tools to replace damaged parts are to be
secured for major safety facilities equipment and parts that are replaceable.
Specific examples include:① Set priorities and conduct recovery work for replaceable equipment and parts in safety
critical facilities. Secure necessary spare parts and tools for exchanging parts.
② Secure necessary spare parts and continue to discuss effective recovery measures.

b.

Secure storage locations - Spare parts described in a) are to be stored dispersedly in multiple
locations that are unlikely to be impacted by external events such as slope failure due toearthquakes, and inundation due to tsunamis.

c.

Secure access routes - Effective operation management is to be conducted so that, should
severe accidents occur, station roads and passageways that can serve as access routes forrecovery work can be secured.

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APPENDIX B – PHASE 2 RESPONSES

3.

Response to supporta.

The station policy is to be able to maintain accident containment response measures for atleast seven days after the day of the accident using the severe accident response equipment,
spare parts, and fuel stored in the station.

b.

The station is to formulate a plan for obtaining external support based on discussions andthe agreement with relevant parties including plant manufacturers, contractors, fuel supply
companies, and other nuclear operators.

c.

The station plans to receive assistance from outside within seven days of the event occurring,such as equipment equivalent to on-site severe accident response equipment, spare parts,and fuel, all of which are stored outside the station.

4.

Development of procedures, implementation of training, and developing a structurea.

Development of procedures
Procedures are to be developed beforehand, training conducted on personnel, and astructure developed to secure necessary personnel in order to be able to respond to severe
accidents flexibly and appropriately.
Specific examples include:① Gathering information and formulating decision criteria
In severe situations such as station blackout, permanent DC power loss, multiple failuresof safety system equipment or instruments, and simultaneous damage incurred to multiple
reactors, the state of commercial power generating reactor facilities need to be assessedand decisions made for severe accident response measures to be implemented. To that end,develop procedures including clear decision criteria, types of information necessary andways to obtain said information so that necessary information can be gathered swiftly.
② Clarifying decision criteria for setting priorities in operations
Develop procedures that clearly stipulate decision criteria for operations such as the use of
seawater that should be prioritized to prevent significant damage to the core or thecontainment vessel failure.
③ Policy of prioritizing safety over protecting property (i.e. facilities)–

The President issues a policy of prioritizing safety over protecting property (i.e.
facilities) so that personnel can develop a common base of understanding on safety
and behave accordingly.

–

Include decision criteria crafted based on the policy of prioritizing safety overprotecting property (i.e. facilities) in procedures so that the Deputy Shift Supervisor
can issue directions without hesitation.

–

The station emergency response headquarters general manager makes decisions
following the policy of prioritizing safety over protecting property (i.e. facilities);
Develop an emergency response headquarters procedures whose decision-making
criteria is based on the policy of prioritizing safety over protecting property (i.e.
facilities).

④ Clarify procedure configuration and criteria for transitioning between procedures–

Develop procedures for operators and support organizations to implement specificsevere accident response following accident progression.

–

Clearly stipulate in the operating procedures about which procedures should be
followed in which order according to accident progression, and clarify the criteria forwhen to transition between procedures.

⑤ Development of procedures related to status monitoring and accident progress
prediction

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APPENDIX B – PHASE 2 RESPONSES–

Select parameters that need to be monitored to respond to severe accidents; list said
parameters in operation procedures and emergency response headquarters
procedures.

–

Organize parameters whose behavior needs to be predicted, items that require
impact assessments, and parameters to be monitored in implementing severe
accident response measures in the emergency response headquarters procedures.

–

Include effective information identified in the effectiveness assessment in theoperating procedures used by operators as well as the emergency response
headquarters procedures used by emergency response personnel.

⓺ Development of response procedures for early signsb.

–Review measures to maintain safety functions of facilities and accident prevention
measures to see if there are early indications of malfunction that can be identified
and if such malfunction could trigger severe accidents–

Develop a structure and procedures that allow for early response when early signs
are identified.

–

Stipulate in procedures that the reactor should be generally shut down and cooling
operations be started if a large tsunami alarm is issued.

Conducting training

The following are examples of implementing training.
① Education and training policy

Conduct education and training to increase personnel knowledge of commercial nuclear
reactor facilities behavior in severe accidents as a wide variety of severe accident response
measures are required depending on the state of the commercial nuclear reactor facility.
② Education to increase knowledge-based understanding and comprehensive exercises

Periodically conduct education to increase knowledge-based understanding of each roleassigned to the personnel e.g. education on severe accidents and fundamental response
methods.
Plan periodic training for the situation where emergency response personnel working on
the field and operators need to cooperate to go through the sequence of response measures,
and arrange exercises to comprehensively confirm the effectiveness of supportingorganizations.
③ Maintenance training

Have employees conduct maintenance and inspection activities and develop experienceexchanging parts to gain more knowledge of the commercial nuclear reactor facility andspare parts.
④ Training assuming high dose conditions

Conduct accident response training assuming high dose conditions, night time andinclement weather.
⑤ Preparations to ensure manuals are readily available

Ensure through maintenance and inspection activities that information and manuals on
facilities and equipment are readily available. Conduct accident response training using
such information and manuals.

c.

Developing a structure
The following are examples of developing a structure.
① Allocation of roles and clarifying the party responsible

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APPENDIX B – PHASE 2 RESPONSES–

Allocate clear roles to organizations implementing the severe accident response
measures and the support organizations providing support to the implementing
organizations. Designate the responsible party for each.

–

Formulate work teams considering the expertise and experience of each personnel.

–

Clarify the chain of command and develop a structure that makes effective
implementation of severe accident response measures possible.

② Configuration of the implementing organization
The organization implementing the severe accident response measures will consist of
the following teams. Roles will be allocated accordingly and a structure will be developedthat allows for the smooth implementation of severe accident response measures.
–

Shift (operators) that will implement operations related to accident impact
mitigation and escalation prevention. A unit team that will provide informationneeded to select appropriate response measures to the shift (operators).

–

Recovery team that will operate the portable severe accident response equipment
related to accident impact mitigation and escalation prevention and recovermalfunctioning equipment–

Self-defense fire brigade to conduct fire extinguishing activities③ Response to situations where multiple reactors are damaged–

The general manager of the station response headquarters will set forth an action
policy when severe accidents occur at multiple reactors. The Unit chief designated foreach reactor will implement severe accident response measures by providing advicefor operations related to accident impact mitigation and escalation prevention for the
relevant reactor, overseeing response using portable severe accident response
equipment and supervising recovery of malfunctioning equipment.

–

Constantly secure station necessary emergency response personnel at the plantand develop a structure that allows the personnel to respond appropriately evenwhen multiple reactors are damaged simultaneously.

④ Configuration of the supporting organization–

Create 1) a engineering support organization that provides technical advice to theimplementing organization and 2) an operation support organization that willdevelop an environment where the implementing organization can concentrate on
severe accident response, as support organizations for the station response
headquarters.

–

The engineering support organization will be comprised of a team that gathers
information necessary for accident response, predicts and assesses plant state
progression, and a team that measures radiation and radioactivity in and outside thestation and controls exposure.

–

The operation support organization will be comprised of a team that gathers external
response information, a team that serves as a contact point for external relevantorganizations, a team that centrally manages procurement and transport, and ateam that supports the operation of the station response headquarters.

⑤ Setting up the response headquarters and gathering personnel

46–

A Plant General Manager (manager of nuclear disaster response) will establish astation response headquarters with an implementing organization and supportingorganizations within it.

–

Emergency response personnel, operators, and self-defense fire brigade will always
be on site premises when the plant is in operation to ensure swift response should asevere accident occur at night time or on weekends (outside of working hours on
weekdays).

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APPENDIX B – PHASE 2 RESPONSES(For multiple units）
There should be approximately 40 emergency response personnel, approximately
20 operators, and 10 members of the self-defense fire brigade for a total of 80
personnel constantly being at the station. A total of 180 personnel should be able tobe gathered within 10 hours of an event occurring. An additional 40 emergency
response personnel should be secured within 6 hours of the event occurring.
–

Conduct periodic communication training based on a predetermined contact
structure to ensure necessary personnel can be gathered even at night time and on
weekends (outside of working hours on weekdays) in emergencies.
The emergency response personnel structure should be managed appropriately to
prepare for the eventuality that there is a vacancy. If a vacancy cannot be filled, thereactor needs to shift to an operational state where safety can be secured with theexisting number of personnel, e.g. stopping a reactor.

⑥ Clarifying the division of roles for each team and the person responsible Clarify thefunctions of teams mentioned in ⑤ above and appoint team leaders and their proxies
as the parties responsible for implementing response measures and for supervising otherteams under their control.
⑦ Clarifying the chain of command and proxies
Clarify the chain of command in the station response headquarters ,appoint proxies, anddefine the order of succession for when the commander is unavailable.
⑧ Preparation of facilities for effective implementation of measures–

Set up an emergency response center equipped with communication facilities(including a TV conferencing system) that allows communication inside and outside
the station and connects to the integrated nuclear disaster response network in orderfor the implementation organization and support organization to implement theirassigned roles.

–

Equip the emergency response center with mobile communication facilities tocoordinate response between the field and the main control room emergency
response center.

⑨ Providing information outside and inside the station
Develop a structure whereby the station can provide information widely through acommunication system that can connect to the integrated nuclear disaster response
network and the satellite phone facilities in order to contact organizations inside andoutside the station on the status of reactor facilities and the implementation of severe
accident response measures.
⑩ Development of external support structures–

Develop structures such as a head office response headquarters for when a nuclear
emergency situation is declared in order to smoothly receive support from outside
the station.

–

The head office response headquarters will be comprised of a team that will review
and formulate station recovery methods, a team that will share information within
the head office response headquarters, a team that will assess the state andprogression of the accident, a team that will assess the amount of radioactive
materials emitted, a team that will communicate with relevant authorities, a teamthat will respond to PR inquiries, a team that will provide support to the station insiting region response, a team that will recover communication facilities and secure
support, a team that will improve the workplace environment of the station, a teamthat will support the development of an on-site medical base, a team that willprocure and transport materials necessary for station recovery, a team that will
establish and operate the nuclear disaster response support base, a team that will
request support from authorities, and a team that will coordinate support received

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47

APPENDIX B – PHASE 2 RESPONSES

from other nuclear utilities. The head office response headquarters will provide
technical and operational support to ensure that the station response headquarters
can concentrate on accident response.
–

The head office response headquarters will establish a nuclear disaster response
support base and develop a structure whereby they can receive engineering support
from other nuclear utilities and from the nuclear emergency situation support
organization.

–

The head office response headquarters will mobilize not only the nuclear divisionbut other divisions so that nuclear emergency response measures can be
implemented as a companywide initiative.

⑪ Development of a structure for mid-to long term response after the accident–

To prepare for situations in which mid-to long term response is required after a severe
accident, develop a structure to implement appropriate and effective responses incoordination with relevant organizations internal and external.

–

Should a severe accident occur, implement measures to reduce radioactivity levels
and process contaminated water that includes radioactive materials leveraging theexperiences and knowledge gained in the Fukushima Daiichi Nuclear Power Station
Accident. Continue to maintain the cooperative relationships with variousorganizations in normal times so that necessary response measures can be discussed
together after an accident to smoothly bring things under control.

3. STAFFING
Necessary personnel structures are to be developed and periodically assessed so that station
maintenance activities can be conducted should a severe accident occur or large-scale damage
be incurred. Necessary measures are to be implemented following this assessment.
Specific examples of structure development are as follows.
(Same as “2. Other procedures and guidelines, (4) Development of procedures, implementationof training, and developing a structure, c. Developing a structure”)① Allocation of roles and clarifying the party responsible–

Allocate clear roles to organizations implementing the severe accident response
measures and the support organizations providing support to the implementing
organizations. Designate the responsible party for each.

–

Formulate work teams considering the expertise and experience of each personnel.

–

Clarify the chain of command and develop a structure that makes effective
implementation of severe accident response measures possible.

② Configuration of the implementing organization
The organization implementing the severe accident response measures will consist of
the following teams. Roles will be allocated accordingly and a structure will be developedthat allows for the smooth implementation of severe accident response measures.
–

Shift (operators) that will implement operations related to accident impact
mitigation and escalation prevention. A unit team that will provide informationneeded to select appropriate response measures to theshift (operators).

–

Recovery team that will operate the portable severe accident response equipment
related to accident impact mitigation and escalation prevention and recovermalfunctioning equipment–

Self-defense fire brigade to conduct fire extinguishing activities③ Response to situations where multiple reactors are damaged

48

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APPENDIX B – PHASE 2 RESPONSES–

The general manager of the station response headquarters will set forth an action
policy when severe accidents occur at multiple reactors. The Unit chief designated foreach reactor will implement severe accident response measures by providing advicefor operations related to accident impact mitigation and escalation prevention for the
relevant reactor, overseeing response using portable severe accident response
equipment and supervising recovery of malfunctioning equipment.

–

Constantly secure station necessary emergency response personnel at the plant anddevelop a structure that allows the personnel to respond appropriately even when
multiple reactors are damaged simultaneously.

④ Configuration of the supporting organization–

Create 1) a engineering support organization that provides technical advice to theimplementing organization and 2) an operation support organization that willdevelop an environment where the implementing organization can concentrate on
severe accident response, as support organizations for the station response
headquarters.

–

The engineering support organization will be comprised of a team that gathers
information necessary for accident response, predicts and assesses plant state
progression, and a team that measures radiation and radioactivity in and outside thestation and controls exposure.

–

The operation support organization will be comprised of a team that gathers external
response information, a team that serves as a contact point for external relevantorganizations, a team that centrally manages procurement and transport, and ateam that supports the operation of the station response headquarters.

⑤ Setting up the response headquarters and gathering personnel–

A Plant General Manager (manager of nuclear disaster response) will establish astation response headquarters with an implementing organization and supportingorganizations within it.

–

Emergency response personnel, operators, and self-defense fire brigade will always
be on site premises when the plant is in operation to ensure swift response should asevere accident occur at night time or on weekends (outside of working hours on
weekdays).
（For multiple units）
There should be approximately 40 emergency response personnel, approximately
20 operators, and 10 members of the self-defense fire brigade for a total of 80
personnel constantly being at the station. A total of 180 personnel should be able
to be gathered within 10 hours of an event occurring. An additional 40 emergency
response personnel should be secured within 6 hours of the event occurring.

–

Conduct periodic communication training based on a predetermined contact
structure to ensure necessary personnel can be gathered even at night time and on
weekends (outside of working hours on weekdays) in emergencies.

The emergency response personnel structure should be managed appropriately to prepare
for the eventuality that there is a vacancy. If a vacancy cannot be filled, the reactor needs toshift to an operational state where safety can be secured with the existing number of personnel,e.g. stopping a reactor.
⑥ Clarifying the division of roles for each team and the person responsible Clarify thefunctions of teams mentioned in ⑤ above and appoint team leaders and their proxies
as the parties responsible for implementing response measures and for supervisingother teams under their control.
⑦ Clarifying the chain of command and proxies - Clarify the chain of command in thestation response headquarters, appoint proxies, and define the order of succession forwhen the commander is unavailable.

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APPENDIX B – PHASE 2 RESPONSES⑧ Preparation of facilities for effective implementation of measures–

Set up an emergency response center equipped with communication facilities(including a TV conferencing system) that allows communication inside and outside
the station and connects to the integrated nuclear disaster response network in orderfor the implementation organization and support organization to implement theirassigned roles.

–

Equip the emergency response center with mobile communication facilities tocoordinate response between the field and the main control room emergency
response center.

⑨ Providing information outside and inside the station
Develop a structure whereby the station can provide information widely through acommunication system that can connect to the integrated nuclear disaster response
network and the satellite phone facilities in order to contact organizations inside andoutside the station on the status of reactor facilities and the implementation of severe
accident response measures.
⑩ Development of external support structures–

Develop structures such as a head office response headquarters for when a nuclear
emergency situation is declared in order to smoothly receive support from outside
the station.

–

The head office response headquarters will be comprised of a team that will review
and formulate station recovery methods, a team that will share information within
the head office response headquarters, a team that will assess the state andprogression of the accident, a team that will assess the amount of radioactive
materials emitted, a team that will communicate with relevant authorities, a teamthat will respond to PR inquiries, a team that will provide support to the station insiting region response, a team that will recover communication facilities and secure
support, a team that will improve the workplace environment of the station, a teamthat will support the development of an on-site medical base, a team that willprocure and transport materials necessary for station recovery, a team that will
establish and operate the nuclear disaster response support base, a team that will
request support from authorities, and a team that will coordinate support received
from other nuclear utilities. The head office response headquarters will provide
technical and operational support to ensure that the station response headquarters
can concentrate on accident response.

–

The head office response headquarters will establish a nuclear disaster response
support base and develop a structure whereby they can receive engineering support
from other nuclear utilities and from the nuclear emergency situation support
organization.

–

The head office response headquarters will mobilize not only the nuclear divisionbut other divisions so that nuclear emergency response measures can be
implemented as a companywide initiative.

⑪ Development of a structure for mid-to long term response after the accident

50–

To prepare for situations in which mid-to long term response is required after asevere accident, develop a structure to implement appropriate and effective
responses in coordination with relevant organizations internal and external.

–

Should a severe accident occur, implement measures to reduce radioactivity levels
and process contaminated water that includes radioactive materials leveraging theexperiences and knowledge gained in the Fukushima Daiichi Nuclear Power Station
Accident. Continue to maintain the cooperative relationships with variousorganizations in normal times so that necessary response measures can be discussed
together after an accident to smoothly bring things under control.

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APPENDIX B – PHASE 2 RESPONSES

4. ORGANIZATIONAL STRUCTURES, COMMUNICATION,
AUTHORITY, AND SAFETY CULTURE

DECISION

MAKING

Necessary structures are to be developed and periodically assessed so that station maintenanceactivities can be conducted should a severe accident occur or large-scale damage be incurred.
Necessary measures are to be implemented following this assessment.
Specific examples of structure development are as follows.
（Same as “2. Other procedures and guidelines, (4) Development of procedures, implementationof training, and developing a structure, c. Developing a structure”）① Allocation of roles and clarifying the party responsible–

Allocate clear roles to organizations implementing the severe accident response
measures and the support organizations providing support to the implementing
organizations. Designate the responsible party for each.

–

Formulate work teams considering the expertise and experience of each personnel.

–

Clarify the chain of command and develop a structure that makes effective
implementation of severe accident response measures possible.

② Configuration of the implementing organization
The organization implementing the severe accident response measures will consist of
the following teams. Roles will be allocated accordingly and a structure will be developedthat allows for the smooth implementation of severe accident response measures.
–

Shift (operators) that will implement operations related to accident impact
mitigation and escalation prevention. A unit team that will provide informationneeded to select appropriate response measures to the shift (operators).

–

Recovery team that will operate the portable severe accident response equipment
related to accident impact mitigation and escalation prevention and recovermalfunctioning equipment–

Self-defense fire brigade to conduct fire extinguishing activities③ Response to situations where multiple reactors are damaged–

The general manager of the station response headquarters will set forth an action
policy when severe accidents occur at multiple reactors. The Unit chief designatedfor each reactor will implement severe accident response measures by providing
advice for operations related to accident impact mitigation and escalation
prevention for the relevant reactor, overseeing response using portable severe
accident response equipment and supervising recovery of malfunctioning
equipment.

–

Constantly secure station necessary emergency response personnel at the plant anddevelop a structure that allows the personnel to respond appropriately even when
multiple reactors are damaged simultaneously.

④ Configuration of the supporting organization–

Create 1) a engineering support organization that provides technical advice to theimplementing organization and 2) an operation support organization that willdevelop an environment where the implementing organization can concentrate on
severe accident response, as support organizations for the station response
headquarters.

–

The engineering support organization will be comprised of a team that gathers
information necessary for accident response, predicts and assesses plant state
progression, and a team that measures radiation and radioactivity in and outside thestation and controls exposure.

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APPENDIX B – PHASE 2 RESPONSES–The operation support organization will be comprised of a team that gathers external
response information, a team that serves as a contact point for external relevantorganizations, a team that centrally manages procurement and transport, and ateam that supports the operation of the station response headquarters.

⑤ Setting up the response headquarters and gathering personnel–

A Plant General Manager (manager of nuclear disaster response) will establish astation response headquarters with an implementing organization and supportingorganizations within it.

–

Emergency response personnel, operators, and self-defense fire brigade will always
be on site premises when the plant is in operation to ensure swift response should asevere accident occur at night time or on weekends (outside of working hours on
weekdays).
（For multiple units）
There should be approximately 40 emergency response personnel, approximately 20
operators, and 10 members of the self-defense fire brigade for a total of 80 personnel
constantly being at the station. A total of 180 personnel should be able to be gathered
within 10 hours of an event occurring. An additional 40 emergency response
personnel should be secured within 6 hours of the event occurring.

–

Conduct periodic communication training based on a predetermined contact
structure to ensure necessary personnel can be gathered even at night time and on
weekends (outside of working hours on weekdays) in emergencies.

The emergency response personnel structure should be managed appropriately to prepare
for the eventuality that there is a vacancy. If a vacancy cannot be filled, the reactor needs toshift to an operational state where safety can be secured with the existing number of personnel,e.g. stopping a reactor.
⑥ Clarifying the division of roles for each team and the person responsible Clarify thefunctions of teams mentioned in ⑤ above and appoint team leaders and their proxies as
the parties responsible for implementing response measures and for supervising otherteams under their control.
⑦ Clarifying the chain of command and proxies - Clarify the chain of command in thestation response headquarters, appoint proxies, and define the order of succession forwhen the commander is unavailable.
⑧ Preparation of facilities for effective implementation of measures–

Set up an emergency response center equipped with communication facilities(including a TV conferencing system) that allows communication inside and outside
the station and connects to the integrated nuclear disaster response network in orderfor the implementation organization and support organization to implement theirassigned roles.

–

Equip the emergency response center with mobile communication facilities tocoordinate response between the field and the main control room emergency
response center.

⑨ Providing information outside and inside the station
Develop a structure whereby the station can provide information widely through acommunication system that can connect to the integrated nuclear disaster response
network and the satellite phone facilities in order to contact organizations inside andoutside the station on the status of reactor facilities and the implementation of severe
accident response measures.
⑩ Development of external support structures

52

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APPENDIX B – PHASE 2 RESPONSES

Develop structures such as a head office response headquarters for when a nuclear
emergency situation is declared in order to smoothly receive support from outside thestation.
–The head office response headquarters will be comprised of a team that will review
and formulate station recovery methods, a team that will share information within
the head office response headquarters, a team that will assess the state andprogression of the accident, a team that will assess the amount of radioactive
materials emitted, a team that will communicate with relevant authorities, a teamthat will respond to PR inquiries, a team that will provide support to the station insiting region response, a team that will recover communication facilities and secure
support, a team that will improve the workplace environment of the station, a teamthat will support the development of an on-site medical base, a team that willprocure and transport materials necessary for station recovery, a team that will
establish and operate the nuclear disaster response support base, a team that will
request support from authorities, and a team that will coordinate support received
from other nuclear utilities. The head office response headquarters will provide
technical and operational support to ensure that the station response headquarters
can concentrate on accident response.

–

The head office response headquarters will establish a nuclear disaster response
support base and develop a structure whereby they can receive engineering support
from other nuclear utilities and from the nuclear emergency situation support
organization.

–

The head office response headquarters will mobilize not only the nuclear divisionbut other divisions so that nuclear emergency response measures can be
implemented as a companywide initiative.

⑪ Development of a structure for mid-to long term response after the accident–

To prepare for situations in which mid-to long term response is required after a severe
accident, develop a structure to implement appropriate and effective responses incoordination with relevant organizations internal and external.

–

Should a severe accident occur, implement measures to reduce radioactivity levels
and process contaminated water that includes radioactive materials leveraging theexperiences and knowledge gained in the Fukushima Daiichi Nuclear Power Station
Accident. Continue to maintain the cooperative relationships with variousorganizations in normal times so that necessary response measures can be discussed
together after an accident to smoothly bring things under control.

With regard to communication, facilities equipped with diversified communication meansare established to make sure that necessary instructions are given to station personnel shoulda design-base accident occur.
Specific examples are as follows;① Facilities with diversified communication means are established as a communication
facilities inside the station.
② A safety parameter display system (SPDS) is installed to transmit data required tounderstand the status of an accident to the emergency response center located in thereactor building.
③ The above-mentioned facilities are connected to an on-site emergency power source oruninterruptable power source.

In addition, dedicated communication lines with diversified communication means are
installed so that the station can make contact with important parties outside the station.
Specific examples are as follows.

① Communication facilities are established to communicate with head office, thegovernment, local authorities, and other related organizations outside the station.

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APPENDIX B – PHASE 2 RESPONSES② Communication facilities equipped with data transmission system and an integrated
nuclear disaster prevention network are established to transmit necessary data to theemergency response support system (ERSS) and other related parties.
③ Communication facilities are designed to be used constantly without being interrupted
by congestion, and are connected to dedicated communication lines equipped withdiversified communication means such as wired, radio, or satellite communication lines.
④ All of the aforementioned facilities are designed to connect to on-site emergency power
supply sources or uninterruptable power supply sources.

Moreover, there are other necessary facilities and procedures provided so that the station
can communicate with important parties inside and outside. ［Art.62］
Specific examples are as follows.
① In addition to the function to communicate with necessary parties inside and outside
the nuclear power station, various facilities as well as procedures are provided, such as
satellite phone equipment, portable power supply system for the emergency response
center in the reactor building, and the 1st gas turbine generator, which enables power tobe supplied to the communication facilities from an alternative power supply system,② Facilities and procedures such as satellite phone equipment and radio link system areprovided to share important parameters measured with important places inside andoutside the station.

Image of enhancement of radio communications

54

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APPENDIX B – PHASE 2 RESPONSES

Image of External Communication

With regard to safety culture, a structure is developed to carry out quality assurance
activities to implement design & construction and operation & maintenance smoothly andsafely. Also, the management assumes a leading role to undertake initiatives such as reform sothat safety culture will take root in the entire organization.
Specific examples are as follows.
① The quality assurance plan is formulated based on “Rules of Quality Assurance for Safetyof Nuclear Power Plants (JEAC4111-2009)” and “Regulations on the method of quality
control of design and construction by licensee of nuclear reactors, and technicalstandards for the licensee to review quality control, regarding commercial nuclear
reactors”, in order to construct a quality management system including efforts to raiseawareness of station personnel to conform to technical specifications and related
ordinances as well as to encourage initiatives to develop safety culture, aiming toachieve, maintain, and improve safety at the nuclear power station.
② The system to document procedures and records is stipulated based on the quality
assurance plan for each department of head office, the power station and the internal
audit office of head office.
③ The president is to develop a policy based on the quality assurance plan, and disseminate
to all employees the importance of nuclear safety. Moreover, under Chief Nuclear Officer(CNO) who is a supervising manager of the implementation party, plant generalmanagers and directors at Head office are to formulate, carry out, evaluate and improveplans related to quality assurance activities implemented at each department, according
to the policy.
④ Head of the internal audit office, a supervising manager of the audit party, is to conduct
an audit independently from the implementation party.

⑤ While a supervising manager of the implementation party is to conduct a self- evaluationof the status of safety culture, a supervising manager of the audit party is to carry out
an independent evaluation of the station’s effort to develop safety culture. An evaluationof safety culture conducted by an external organization is also subject to the audit.
⑥ The president receives a report about the quality assurance activities from supervising
managers, and conducts a management review about the necessity of further
improvement based on the report.
⑦ Moreover, activities common among the implementation party are reviewed bysupervising managers at head office, and activities conducted by the station are
examined at the plant general manager review. The results of both reviews are to bereflected into each duty aiming to maintain and improve the effectiveness of the quality
management system.

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APPENDIX B – PHASE 2 RESPONSES

5. PERSONNEL QUALIFICATIONS AND TRAINING
Station engineers receive education and training to maintain and improve their expert
knowledge and technical skills.
Specific examples include:
1. Conduct fundamental education and training for newly deployed engineers to ensurethat they obtain fundamental knowledge regarding nuclear power generation.
2. Engineers that will be involved in design & construction and operation & maintenancewill receive desktop education and practical training at external domestic nuclear
power-related organizations according to their capabilities, in addition to training at
station facilities, to ensure that they gain the necessary expert knowledge and technicalskills.
3. Formulate education and training implementation plans that stipulate specific matterssuch as persons subject to such training, the content, and frequency of training
depending on the level of expert knowledge and the technical skill of personnel.
4. Engineers that will respond to natural disasters and severe accidents, personnel incharge of administrative matters, and contractor employees will receive the necessary
education and training according to their roles.
5. In addition to the above, a Nuclear Human Resource Development Center has been
established to conduct systematic education and training to increase the base level oftechnical skills, based on the realization that an attitude of formulating countermeasuresat one’s own initiative and swiftly preparing for future developments was lacking in the
TEPCO Fukushima Nuclear Power Station Accident. Initiatives are being undertaken toincrease technical capabilities at the Center.
Procedures are developed in advance and training conducted for the station to be able torespond appropriately and flexibly to severe accidents.
Specific examples include:
1.

Education and training implementation policy
Conduct education and training to increase operator’s knowledge of generating nuclear
reactor facility behavior in severe accidents, as a wide variety of countermeasures arenecessary for severe accident depending on the state of the reactor.

2. Conduct education and comprehensive exercises to increase knowledge-based
understanding① Conduct periodic education for personnel to improveknowledge-based
understanding of severe accidents and basic response methods according to theirroles.
② Periodically plan exercises to comprehensively confirm the effectiveness of theimplementing organization and supporting organization, and training given to theemergency response personnel on the field and the operators to learn how tocooperate in carrying out a series of response measures.
3. Maintenance training
Have employees conduct maintenance and inspection activities and develop experienceexchanging parts to gain more knowledge of the commercial nuclear reactor facility andspare parts.
4. Training assuming high dose conditions
Conduct accident response training assuming high dose conditions, night time andinclement weather.
5. Preparations to ensure manuals are readily available

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APPENDIX B – PHASE 2 RESPONSES

Ensure through maintenance and inspection activities that information on facilities andequipment and manuals are readily available. Conduct accident response training using
such information and manuals.
Conduct education and training assuming large-scale damage, in addition to those related
to severe accident response, for operators, emergency response personnel and self-defense firebrigade (including contractor employees) designated to respond to large-scale damage.
Conduct individual training and education for the Nuclear Emergency Preparedness
Manager and their proxy, assuming that normal chains of command may not be functioning inlarge scale disasters.
Enhance education and training so that operators and emergency response personnel can
execute response measures beyond their assigned roles, by ensuring that they acquirecapabilities to respond flexibly to the situation.

6. PLANT INSTRUMENTATION, CONTROLS, HUMAN-SYSTEM INTERFACES, AND
COMMUNICATIONS EQUIPMENT
The station has facilities and procedures necessary in assessing data for estimating parameters,
should parameters that need to be monitored to respond to severe accidents become difficult tomeasure due to instrument failure.
Specific examples include:
1. Should the state of the station exceed the station’s capabilities to grasp the situation (e.g.
exceed maximum measurable temperature), estimate parameters to assess the state of
the generating nuclear reactor facility and set priorities for the parameters to be
estimated. To this end, select important monitoring parameters, designate instrumentsthat measure alternative parameters as severe accident response equipment, and deploy
portable measuring equipment as severe accident response equipment.
2. Provide power should power for instrumentation be lost. To that end, deploy portable
instruments, permanent alternate AC power sources and power supply trucks as severe
accident response equipment.
3. Record parameters in severe accidents. To that end, deploy SPDS display devices as partof a safety parameter display system, and a data transmission device and an emergency
response support system transmission device as severe accident response equipment.
4. Estimate and monitor parameters using other channels to assess the state of thegenerating nuclear reactor facility, should instruments to measure those parameters
necessary for severe accident response fail. Designate important instruments andimportant alternative instruments of the other channel as severe accident response
equipment.
The station has developed facilities and procedures necessary to communicate withlocations inside and outside the station as necessary.
Specific examples include:
1. Communicate with locations inside and outside the generating nuclear reactor facility
as necessary and receiving power from alternative power supply sources. To that end,
deploy satellite telephone equipment, wireless communication equipment, mobile
telephone equipment, communication equipment that uses the integrated nuclear
power emergency preparedness network, safety parameter display system (SPDS),
portable power sources for the emergency response center, and gas turbine generators
as severe accident response equipment.
The satellite telephone equipment, wireless communication equipment, mobile
telephone equipment, communication equipment that uses the integrated nuclear
power emergency preparedness network, and safety parameter display system (SPDS)
will receive power from the alternative power sources to ensure power source diversity.

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APPENDIX B – PHASE 2 RESPONSES

2. Share important parameters measured with relevant organizations. To that end, deploy
satellite telephone equipment, wireless communication equipment, mobile telephoneequipment, and communication equipment that uses the integrated nuclear power
emergency preparedness network as severe accident response equipment.
The satellite telephone equipment, wireless communication equipment, mobile
telephone equipment, communication equipment that uses the integrated nuclear
power emergency preparedness network, and safety parameter display system (SPDS)
are designed to use different communication methods.

7. PORTABLE EQUIPMENT/TOOLS, PROTECTIVE GEAR, AND WORK ENVIRONMENTS
Portable equipment to be used in large-scale damages and severe accidents are designed asfollows.
1. Capacity
The portable severe accident response equipment will have the necessary capacity
according to the objective of the system, taking into account assumed severe accident
and the accident progression. The station will also secure enough portable severe accident
response equipment, including spare equipment, and consider the function andreliability of the equipment so that the station will not only have the minimum necessary
capacity but capacity with additional margins.
2. Secure connection
When connecting portable severe accident response equipment to permanentequipment, use bolts or screws to connect cables to ensure connection is easy and secure.
Use flanges to connect large diameter pipes or in high pressure environments, andsimpler connecting methods for low small diameter pipes and in low pressure
environments, according to the diameter of pipes or the pressure of inner fluids. To
ensure that portable severe accident response equipment can be used interchangeably
within the site, the station will endeavor to use thesame connection methods acrossmultiple systems, e.g. the same shapes will be used for multiple units within the site,
same diameter pipe used to connect the same pumps.
3. Multiple connection ports
Connecting ports that connect permanent equipment with portable severe accident
response equipment to supply water or power from outside the reactor building will be
installed in multiple isolated locations indoors or outdoors on different sides of thebuilding to prevent them from becoming unusable due to common cause such as
intentional crashing of a large airplane or other acts of terrorism.
4. Working environment on the field
Areas that are assumed to have low radiation levels in a severe accident will be selected
as portable severe accident response equipment installation sites and shielding installedon the location so that portable equipment can be installed or connected with permanentequipment safely even if severe accidents occur.
5. Storage location
Portable severe accident response equipment will be stored in multiple locations at least
100 m or more away from the reactor building, turbine building and waste processingbuilding, and also 100m away from outdoor design basis facilities and permanent severe
accident response equipment whose functions the portable severe accident response
equipment will be replacing, considering the impact of natural disasters such as
earthquakes and tsunamis, acts of terrorism such as the intentional crashing of a large
airplane, the location of design basis accident response facilities and permanent severe
accident response equipment, and other conditions.

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APPENDIX B – PHASE 2 RESPONSES

6. Securing access routes
The station will ensure that station roads and passageways will be able to be secured ina severe accident to transport portable severe accident response equipment and to grasp
the damages done to other equipment.
The station will secure multiple routes to transport the portable severe accident response
equipment from the storage place to its installation location or connecting locationindoors or outdoors, other access routes to assess the damages done to other facilities,
and their detours in the event that natural disasters, external man-induced events,
inundation, and fires occur.
Wheel loaders that can remove obstacles will be stored and used as necessary to secure anaccess route that can be recovered the quickest among multiple access routes in theevent earthquakes and other natural disasters impact outdoor access routes.
7. Design basis accident response equipment and permanent severe accident prevention
equipment, and their diversity
Portable severe accident response equipment is designed considering diversity,
independence, geographical decentralization to ensure that common causes such asenvironmental conditions, earthquakes, tsunamis, and other natural disasters, external
man-induced events, inundation, fires and support system failures do not cause function
loss of the portable severe accident response equipment, design basis accident response
equipment, and permanent severe accident prevention equipment simultaneously.
The reactor control room has facilities and procedures necessary for operators to remain attheir positions even in a severe accident.
Specific examples include:
1.

Secure livability of the main control room and protect operators from radioactive
materials emitted into the environment in severe accidents by installing shielding in themain control room, shielding in the waiting room for the main control room, portable
positive pressure air conditioner, and the positive pressurizer. To that end, deploy
shielding of the waiting room for the main control room, portable positive pressure air
conditioner, and a positive pressurizer as severe accident response equipment anddesignate the shielding of the main control room as a severe accident response
equipment. Develop procedures to have operators wear full face masks and a develop a
structure for shift turnover to ensure that operator effective exposure dose does notexceed 100mSv over seven days in any accident sequence.

2. Reduce operator exposure from the radioactive materials emitted into the environmentor the secondary containment facility in a severe accident using the emergency gas
processing system. The emergency gas processing system is designated as a severe
accident response equipment.
3. Check the concentration of gasses in the main control room using an oxygen content
meter and carbon dioxide content meter. To that end, deploy an oxygen content meterand carbon dioxide content meter as severe accident response equipment.
4. Secure lighting in the main control room via portable lighting with a built-in battery.
Deploy portable lighting with a built-in battery as a severe accident response equipment.
5. Set up a changing area to prevent contamination from entering the main control area.

8. WORK PLANNING,
FACILITIES1.

TECHNICALSUPPORT,

AND

EMERGENCYRESPONSE

Engineering support

The station is to establish supporting organizations to be able to respond appropriately andflexibly to severe accidents. Supporting organizations consist of a engineering support
organization that will provide technical advice to the implementing organization and an

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APPENDIX B – PHASE 2 RESPONSES

operational support organization that will provide an environment in which the implementing
organization can concentrate on safety or accident response.
The supporting organization policy is to communicate the state of the generating nuclear
reactor and severe accident response implementation measures to organizations inside andoutside the station and to develop a structure in which it can provide information widely.
Specific examples include:① Configuration of supporting organizations–

An engineering support organization that provides technical advice to theimplementing organization and an operational support organization that willdevelop an environment in which the implementing organization can concentrateon severe accident response will be established in the station response headquarters
as supporting organizations.

–

The engineering support organization will consist of a team that gathers informationnecessary for accident response, predicts and assesses accident progression and ateam that measures radiation and the status of radioactivity inside and outside thestation and conducts exposure management.

–

The operational support organization will consist of a team that will gather external
response information, a team that will communicate with external relatedorganizations, a team that will centrally manage procurement and transport, and ateam that will conduct station response headquarters operational support.

② Development of a support structure for receiving external support–

Establish necessary structures, e.g. a head office response headquarters to smoothly
receive support from outside the station if a nuclear emergency situation is declared.

–

The head office response headquarters will be comprised of a team that wilreview
and formulate station recovery methods, a team that will share information
within the head office response headquarters, a team that will assess the state andprogression of the accident, a team that will assess the amount of radioactive
materials emitted, a team that will communicate with relevant authorities, a teamthat will respond to PR inquiries, a team that will provide support to the station
responding to the plant siting region, a team that will recover communication
facilities and secure support, a team that will improve the workplace environment of
the station, a team that will support the development of an on-site medical base, ateam that will procure and transport materials necessary for station recovery, a teamthat will establish and operate the nuclear disaster response support base, a teamthat will request support from authorities, and a team that will coordinate support
received from other nuclear utilities. The head office response headquarters will
provide engineering and operational support to ensure that the station response
headquarters can concentrate on accident response.

–

The head office response headquarters will establish a nuclear site disaster
response support base and build a structure to receive engineering support fromother nuclear operators and nuclear emergency situation support organizations.

–

The head office response headquarters will conduct nuclear disaster response
activities as a company-wide initiative.

2. Emergency response center
Facilities and procedures to implement appropriate severe accident response measures, shoulda severe accident occur, are deployed to emergency response centers.
The emergency response center will be set up to prepare for the establishment of theemergency response headquarters.

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APPENDIX B – PHASE 2 RESPONSES① Response and facilities
A response headquarters to provide necessary severe accident response instructions andcommunicate with organizations inside and outside the station, and waiting area toaccommodate personnel, will be established inside the emergency response center.
Specific examples include:–

Receive power from alternative power sources. Deploy portable power supply
equipment and tanker trucks for the response headquarters and for the waiting area
as severe accident response facilities, and designate light oil tanks as severe accident
response facilities.

–

Secure the livability of the emergency response center. In the emergency response
center (response headquarters), install an airtight chamber, inner shielding, portable
positive pressure air conditioner, positive pressurizer (air tanks), carbon dioxide
absorption device, portable outside air intake blower, oxide content meter, carbon
dioxide content meter, portable area monitor, portable monitoring post, and adifferential pressure gauge as severe accident response facilities.

–

Be able to accommodate enough personnel at the response headquarters to be able
to respond appropriately to severe accidents. Deploy emergency response personnel
gear (dosimeter and masks), materials necessary to examine severe accident
response, enough water and food to live on for a week without external support, andequipment/materials for the changing area for the response headquarters and thewaiting area.

–

Gather information necessary to issue instructions to respond to the severe accident.
Deploy the SPDS display devices that constitute the safety parameter display system(SPDS), data transmission devices, and emergency response support systemtransmission device as severe accident response facilities.

–

Deploy satellite phones, wireless communication facilities, and communication
facilities that connect to the integrated nuclear disaster response network as severe
accident response facilities in the response headquarters so that the response
headquarters will be able to contact organizations inside and outside the reactor
facilities as needed. Deploy outdoor emergency contact inner phones and mobile
radios as severe accident response facilities to communicate with the area outside
the first floor of the reactor building, the response headquarters, the waiting area, andthe main control room.

② Design policy for severe accident response facilities
Examples of design policies adopted for severe accident response facilities indicated in ①
include:–The facility is designed so as not to lose function in seismic forces due to design basis
ground motions and is installed in a location that will not be affected by design basis
tsunamis.

–

The facility will be in an area far apart from the main control room to ensuregeographical decentralization to account for risk.

–

Backups for portable power supply equipment will be stored in the emergency
response center to protect against failure and to ensure redundancy.

To secure livability and ensure that emergency response personnel, self- defense fire brigade
personnel and operators can stay at the emergency response center, the emergency
response center will be airtight and will be designed to have shielding and ventilationequipment so that the effective exposure dose of emergency response personnel staying at
the emergency response center will not exceed 100mSv in the seven days after the accident.

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APPENDIX B – PHASE 2 RESPONSES③ Procedures
The station has established procedures using the equipment given in ① above. Specificexamples include:•

Procedures for supplying power from alternative power supply equipment
–

•

•

•

62

Start on procedures for providing power from the emergency response centerportable
power supply equipment when establishing an emergency response center.

Procedures for securing livability–

Start on procedures for operating the emergency response center portable positive
pressure air conditioner when establishing the emergency response center.

–

When making the decision to conduct containment vessel venting after core damage,
start on procedures to increase pressure in the emergency response center via theemergency response center positive pressurizer (air tanks) and stop the emergency
response center portable positive pressure air conditioner.

–

If a reduction in the radioactive materials in the surrounding environment isconfirmed via the portable monitoring post or the monitoring post, start on
procedures to start up the portable positive pressure air conditioner and shut down
the emergency response center positive pressurizer (air tanks).

–

If portable or stationary monitoring posts show that the radioactive materials in thesurrounding environment are sufficiently reduced but the atmospheric dose inside
the building is higher than the dose outdoors, start on procedures to ventilate thecorridors that serves as an air supply area for the emergency response center
portable positive pressurizer air conditioner.

–

When a radioactive plume is passing over the area, emergency response–

personnel who will be issuing severe accident response instructions or will beworking to reduce the scattering of radioactive materials outside the station due todamages done to the containment vessel are required to reside in the command
center or the waiting area.

Procedures related to accommodating necessary numbers of personnel–

If a severe accident occurs and containment vessel atmospheric radiation levelmonitors show that core damage has been sustained, start on procedures related tothe operation of the changing area including covering the walls and floors, andinstallation of air tents and various equipment.

–

Deploy to the response center emergency response personnel gear (dosimeter andmasks) and store at least one week’s worth of supplies such as water and food,necessary to accommodate emergency response personnel without outside support
for at least a week. Maintain and manage such supplies.

Procedures related to assessing information necessary for responding to severe accidents
and communication–

One emergency response personnel will operate the safety parameter display
system (SPDS) when establishing the emergency response center.

–

Deploy to the response center materials expected to be required in discussions
following severe accidents. Maintain and manage such materials to ensure they are
up to date.

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APPENDIX B – PHASE 2 RESPONSES

9. EMERGENCY RESPONSE PLANS
10. EXTENDED (LONGER-TERM) RESPONSE
Based on the Act on Special Measures Concerning Nuclear Emergency Preparedness, operators
have created a nuclear operator disaster response work plan with the aim of smoothly andappropriately implementing nuclear disaster countermeasures. This plan covers, for eachnuclear power plant, work necessary in preventing the occurrence and spread of a nuclear
disaster and recovering from a nuclear disaster.
The following are examples of the items listed in the nuclear operator disaster response work
plan.
【Examples listed in the nuclear operator disaster response work plan】
1.

Implementation of nuclear disaster prevention measures•

Disaster prevention framework•

Operation of the nuclear disaster prevention organization•

Preparation of radiation measuring equipment and nuclear disaster prevention
materials•

Preparation of materials to be used in nuclear disaster response activities•

Development and inspection of equipment and facilities to be used in nuclear disaster
response activities•

Implementation of disaster response education•

Implementation of training•

Coordination with related organizations•

Public relations activities targeting residents around the station in ordinary times

2. Response in alert-level events•

Reporting and communication•

Implementation of emergency measures

3. Implementation of emergency response measures•

Reporting and communication•

Implementation of emergency measures•

Emergency response measures

4. Nuclear disaster ex-post measures•

Station measures•

Sending nuclear disaster response personnel

5. Others•

Cooperating with other nuclear operators

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APPENDIX B – PHASE 2 RESPONSES

Korea

Lesson Learnt: KR-01 – Stress Test
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:* Objective of Stress test in Korea’s nuclear power plants.
To evaluate plant response to extreme natural hazards exceeding design basis as a way toreassess the safety of operating nuclear power plants and to find the safety improvement items.
* Scope of Stress test
- SSCs’ integrity against BDBA extreme natural hazards evaluation- Coping capabilities to loss of safety functions- Severe accident management capability evaluation- Emergency preparedness and accident management capability evaluation
Supplemental Files: Stress Test summary report (Only Hanul unit 3 report is available in English)
Anticipated Benefits: Identification of nuclear power plants’ capability to cope with extreme
natural hazards exceeding design basis Identification of nuclear power plants’ safety
improvement items
The events described in this lesson learnt occurred: Korea from 2013 to 2019

Lesson Learnt: KR-02 – Preparation for prolonged emergency
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification

66

Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Securing additional equipment to prepare for a prolonged emergency
Before the Fukushima Daiichi Accident, pursuant to the radiological emergency plan, the KHNP
kept approximately 350 units of seven different types of radiation (radioactivity) instruments
including high-level beta-gamma dose rate meters, 8,600 pieces of radiation production
equipment including protective clothing, 166,000 tablets (130g) of thyroid protection medicine.
In response to a prolonged emergency like the nuclear accident in Fukushima, the KHNP has
additionally secured 440 units of radiation (radioactivity) instruments and 20,000 radiation
protection gears to increase inventory 200% of the previous level.
Supplemental Files: None
Anticipated Benefits: Improvement of radiological emergency plan
The events described in this lesson learnt occurred: Korea, 2013

Lesson Learnt: KR-03 – Reinforcing emergency exercise
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Reinforcing radiation emergency exercise
The KHNP has conducted an unannounced radiation emergency exercise at each nuclear powersite once a year. Unannounced means the personnel participating in the exercise must not be
advised in advance, of the exact date, time and scenario of the exercise. Therefore, it is believedthat the unannounced exercise contributes to strengthening emergency response capabilities
of radiological emergency staff. Furthermore, research was conducted to develop exercise
scenarios based on earthquake and tsunami. The newly developed scenarios have already been
applied in the unified emergency exercise.

Photo example of emergency exercise

Supplemental Files: None
Anticipated Benefits: Improvement of capability to cope with emergency situation
The events described in this lesson learnt occurred: Korea, 2013

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: KR-04 – Mobile power generating equipment
Applicability
Type of Response
On-site Response(Mitigating Event)Off-site Response(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Devising a means for securing necessary information in case of a prolonged loss of electricalpower
The power supply to emergency response facilities as well as the main computer is essential for
acquisition of key plant parameters in case of a prolonged loss of power. The EDG together with
the UPS is secured to prepare for the loss of power to emergency response facilities, however
the UPS alone is not sufficient in case of a long-term loss of power. To resolve the issue, thelicensee completed additional deployment of mobile power generating equipment to ensure
continued power supply to the main computer in 2015.
Supplemental Files: None

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APPENDIX B – PHASE 2 RESPONSES

Anticipated Benefits: Improvement of emergency response facilities
The events described in this lesson learnt occurred: Korea, 2015

Lesson Learnt: KR-05 – Emergency plan for emergency at multiple units
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns

70

Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:- Amending the radiological emergency plan to include such events as the simultaneous
declaring of an emergency at multiple units
The radiological emergency organizations were structured to cope with a radiologicalemergency at a single unit. Now, the radiological emergency organizations are restructured
based on three scenarios: first, a radiological emergency at single unit, second, simultaneous
emergencies at two units on the same site, and third, simultaneous emergencies at all units on
the same site, and the revision of the radiological emergency plan to incorporate the plan forestablishing a radiation emergency organization based on three scenarios has been alreadycompleted in December 2011.
In the revised radiological emergency plan, the magnitude of tsunami is added to the criteria
for declaring an emergency with respect to a natural disaster. In addition, the revised
radiological emergency plan defines the target time for emergency response: issuing a radiation
emergency alert within 15 minutes after detection, initiating radiation emergency organizations
within one hour after the declaration of a radiation emergency and putting the emergency
organizations into operation within two hours.
Supplemental Files: None
Anticipated Benefits: Improvement of capability to cope with emergency situation of multiple
units
The events described in this lesson learnt occurred: Korea, 2011

Lesson Learnt: KR-06 – Response Form - Seismic alarm in MCR
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Improvement of seismic capacity of the seismic alarm window in the main control room
Seismic capacity of the safety-related systems necessary to achieve and maintain safe
shutdown, the SSCs necessary to maintain the integrity of spent fuel pool, and the SSCs
necessary to maintain containment function under a beyond design basis earthquake will be
improved up to the seismic design level of newly constructed nuclear power plants (0.3g).
The seismic performance evaluation is currently conducted using EPRI NP-6041, seismic
probabilistic safety assessment (S-PSA) or seismic margin analysis (SMA). Nuclear systems
which are deficient in seismic capacity should be reinforced. If necessary, the seismic capacityof such system was strengthened.
Installation of seismically qualified seismic alarm equipment and drop prevention measures toprotect MCR operators such as applying seismic design to ceilings and lighting and improving
lighting facilities were completed.

Photo of automatic seismic trip system and alarm in MCR

Supplemental Files: None
Anticipated Benefits: Improvement of seismic capacity of nuclear power plants
The events described in this lesson learnt occurred: Korea, 201472

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: KR-07 – Education and Training
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Reinforcing education and training on severe accident
Actions to strengthen training and education on severe accident were taken to ensure theoperator's prompt response to a severe accident. The refresher training course for operators
was revised to incorporate more training time, increased from 8 hours in every two years to 10
hours every year, and the severe accident training will also be provided to the essential staff ofTechnical Support Center in connection with the operator refresher training. In addition, severe

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APPENDIX B – PHASE 2 RESPONSES

accident scenarios were developed to improve severe accident theories and computer code
practice so as to nurture severe accident experts. They will also be used to identify thecharacteristics of progress of severe accidents for each initiating event and those when
operators' action was taken in accordance with SAMG.
Supplemental Files: None
Anticipated Benefits: Operators and staffs will identify and understand the characteristics ofprogress of severe accidents and SAMG.
The events described in this lesson learnt occurred: Korea, 2013

Lesson Learnt: KR-08 – SAMG revision
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

74

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:- Revision of the Severe Accident Management Guidelines to enhance effectivenessA detailed evaluation methodology for the possibility of core melt cooling by filling the reactor
cavity with water was be determined. The possibility of filling the reactor cavity with water was
reviewed in parallel with plant walkdown. In addition, the availability and cooling capacity interms of filling water flow, filling time and the maximum filling water level were evaluated. At
the same time, a temporary EOP was developed to ensure review and implementation ofeffective filling water flow path. Furthermore, the feasibility of external reactor vessel coolingand the likelihood of side effects resulting from filling the reactor cavity with water including
steam explosion were also evaluated.
Supplemental Files: None
Anticipated Benefits: Identification of the effectiveness of SAMG
The events described in this lesson learnt occurred: Korea, 2015

Lesson Learnt: KR-09 – Low power shutdown SAMG
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Development of Low-Power Shutdown SAMG
Low-Power Shutdown SAMG was developed to improve severe accident response capabilities
during low-power shutdown operation like the Fukushima accident. Generic Low-Power
Shutdown SAMG had been developed in the late 2012 and based on that, specific Low-Power
Shutdown SAMG was developed, and then the full power SAMG and the "Low-Power Shutdown
SAMG" were integrated by the late 2015.
Supplemental Files: None
Anticipated Benefits: Improvement of the SAMG
The events described in this lesson learnt occurred: Korea from 2012 to 2015

Lesson Learnt: KR-10 – Improving the emergency response facilities
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories

76

Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Improving the emergency response facilities
A plan to improve the habitability and the size of emergency response facilities including
Technical Support Center (TSC) and Operation Support Center (OSC) and to prevent inundationof emergency facilities due to a large tsunami was development in the late 2015. In addition,
Mobile Radiation Monitors were deployed to transmit radiation monitoring data using mobile
communication.

Supplemental Files: None
Anticipated Benefits: Improvement of emergency response facilities
The events described in this lesson learnt occurred: Korea, 2015

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: KR-11 – Assessment of manpower
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other] Staffing

Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other] Staffing

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Assessment of adequacy of operating manpower
For the diagnosis of safe operating capacity of nuclear power plants conducted in 2011, task
analysis was performed for organizations of nuclear power plant in operation or at each stageof pre-startup operation. Based upon the results, areas for improvement concerning the proper
staffing level and human resource planning for nuclear power plants were identified andimprovements were made in the standard job classification system, the calculation of proper
manpower, and the establishment of human resource planning for nuclear power plants.
Additionally, a 'Power Generation Personnel Management' system was constructed to prevent

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APPENDIX B – PHASE 2 RESPONSES

the dilution of expertise and knowledge of the staff due to the growing number of new andinexperienced employees at the plants and to provide quantitative criteria to determine theproper ratio of experienced personnel for each power plant. The system helps the KHNP todetermine the adequacy of manpower and to assign personnel to each nuclear power plant.
Supplemental Files: None
Anticipated Benefits: Assessment of adequacy of operating manpower
The events described in this lesson learnt occurred: Korea from 2011 to 2013

Lesson Learnt: KR-12 – Development of accident coping strategies
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
Extreme natural hazards can affect other sites and off-site organization, making it difficult toprovide support to nuclear power plants. Even in that case, as described previously, nuclear
power plants have protective equipment sufficient enough to protect on site personnel. In
response to an extreme natural hazard, KHNP has established MACST (Multi-Barrier Accident
Coping Strategy) through which emergency response up to 72 hours after the onset of an
extreme natural hazard event is made using onsite equipment. It has been assessed that 72
hours is sufficient to secure an access route for off-site personnel and equipment.
In order to cope with extreme external events, 3-phases of coping strategies are developedwith MACST equipment.
Phase 1: Initially cope with equipment in a plant such as tank, piping, battery, pump, etc.
within 8 hours of the accident.
Phase 2: Cope with equipment in a site such as mobile generator, mobile pump, etc. between
8~72 hours after accident.
Phase 3: Cope with every available equipment in a plant, in/out a site after 72 hours after
accident.
For the coping strategy, MACST Operating Guides (MOGs) are prepared and Table shows the
purpose of each MOGs.

1. Diagram of MACST core cooling strategies

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APPENDIX B – PHASE 2 RESPONSES

2. Table of MACST procedures

Supplemental Files: None
Anticipated Benefits: Improvement of capability to cope with extreme natural hazards
The events described in this lesson learnt occurred: Korea, 2016

Lesson Learnt: KR-13 – Accident Management Program
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
To cope with BDBA (Beyond Design Basis Accident) and to improve capability of accident
management, KHNP developed AMP (Accident Management Program).
Before AMP, some of safety measures for BDBA were pushed forward in accordance with postFukushima action and stress test. After AMP, every scope of BDBA will be managed by integrated
AMP.
Supplemental Files: PPT material for Accident Management Program
Anticipated Benefits: Improvement of capability to cope with BDBA
The events described in this lesson learnt occurred: Korea, 2019

Lesson Learnt: KR-14 – Mobile Equipment
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations

82

Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]

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APPENDIX B – PHASE 2 RESPONSES

Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- MACST (Multi-barrier Accident Coping STrategy) equipment
MACST equipment for Phase-1(~8 hr) are stored inside each unit to use as soon as possible.
Except the pre-staged equipment, other mobile equipment for Phase 2(~72 hr) & 3 (72 hr~) arestored in the seismic designed integrated storage building which is constructed for each site.
Besides the MACST equipment for essential safety functions, subsidiary equipment is also
stored in the integrated storage building such as multi-purpose communication unit,
emergency lighting, tractor, wheel loader, etc. The integrated storage building has maintransportation rout along with an alternate one.
* Pre-staged Middle Generator
The capacity is 400 kW enough to supply electrical power for the battery charger, SIT isolation
valves, mobile air compressor, temporary fans, etc. Even though the permanent battery hascapability to supply DC power more than 8 hours by load shedding, the early charging of battery
increases the credibility of coping capability. Therefore, the generator is pre-staged in thevicinity of Auxiliary Building to remove the uncertainty of transportation and supplies electrical
power within 2 hours. 2 operators are supposed to start the generator and supply the electrical
power. One middle generator per unit is pre-staged and anchored on the seismic designed
pedestal considering external flooding.
* Mobile Air Compressor
The capacity is 11.6 scfm with 90 psig enough to supply compressed air for the air operating
valves needed for essential safety function. For the minimization of size and weight, it supplies
compressed air to the target header line by isolating other non-essential air consuming headers.
For the easy and fast use, it is equipped with wheels to move by one operator. One compressor

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APPENDIX B – PHASE 2 RESPONSES

is stored for each unit required in the vicinity of target header line inside the building.
Considering fire and exhaust fumes, it uses electrical power supplied by non-permanent
generators such as pre-staged generator.
* High Pressure Mobile Pump
The high-pressure mobile pump has the capacity of 44 gpm with 1,500 psig in order to injectcoolant into primary side to compensate for the leakage from RCPs and the coolant shrinkage
during cool down. The pressure decrease in primary side and permanent piping design
conditions are considered for the pump discharge pressure. Before the external injection
operation, SITs makeup the RCP leak and coolant shrinkage passively for more than 8 hours(almost 30 hours). One high pressure mobile pump per unit is stored in the integrated storage
building. It will be moved from the building to the pre-determined place. 1 driver and 4 operators
are supposed to move and connect the mobile pump.
* 1.0 MW Mobile Generator
The mobile generator has the capacity of 1.0 MW to supply electrical power for the safety-related
A or B bus at the ELAP accident. It has enough capacity for the battery charging, MCR HVAC, etc.
It will be operated during 8 to 72 hours after the accident. One 1.0 MW mobile generator per unit
is stored in the integrated storage building. 1 driver and 17 workers are supposed to move andconnect the mobile generator.
* 3.2 MW Mobile Generator
The mobile generator has the capacity of 3.2 MW to supply electrical power for the safety-related
A or B bus at the ELAP accident. It has enough capacity for all essential equipment of coolingpumps, motor operated valves, HVAC, etc. The duty is to cool down the plant to the cold
shutdown status after 72 hours of accident. However, like the pre-staged middle generator, prestaged and pre-wired electrical lines of 3.2 MW generator can reduce the coping time drasticallyand remove the uncertainty of transportation. A few (2 or 3 operators can start the generator
and supply the electrical power instead of 18 workers. Two 3.2 MW mobile generators are placedfor each site. They are pre-staged with pre-installed cables even though they have still
movability. Unlike the pre-staged middle generator, the 3.2 MW mobile generators are staged
on the remote area more than 100 meters from the unit and they use the long pre-installedcables. The remote area has dedicated fuel tank with a protection dike. The 3.2 MW mobile
generators are commercial grade and non-seismic, but the pre-staged foundation, fuel tank, anddike are seismic designed.
* High Capacity Mobile Pump (for CCWHX)
The mobile pump has the capacity of 5,000 gpm to supply cooling water for the CCW heatexchanger. The actual capacity can be modulated depending on each plant’s decay heat. The
duty is to cool down the plant to the cold shutdown status after 72 hours of accident. One highcapacity mobile pump per unit is stored in the integrated storage building and 1 driver and adozen workers are supposed to move and connect the pump.
* Mobile Heat Exchanger
The stress test shows that the CCW heat exchangers have enough HCLF value considering
10,000 years return period of seismic events and the earthquake induced tsunami will notinundate the ground level of plants. Even though, there is extremely low possibility to break or
block CCW heat exchangers, each site prepares the mobile heat exchangers. The heatexchanger capacity of 4.0 MBtu/hr℉ is sufficient to remove decay h eat from the reactor
after 72 hours of accident. One mobile heat exchanger per unit is stored in the integrated
storage building. For the use of mobile heat exchanger, the high capacity mobile pump shouldbe accompanied. Therefore, several drivers and a dozen workers are required to move themand connect mobile hoses.
Supplemental Files: PPT material to introduce MACST equipment
Anticipated Benefits: Improvement of capability to cope with BDBA
The events described in this lesson learnt occurred: Korea, until 2024

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: KR-15 – MACST Team
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:- Setup of MACST(Multi-barrier Accident Coping STrategy) Team
MACST team will be set up to be responsible for MACST equipment operation of Warehouse
under head of nuclear site.
In case of nuclear accident, Radioactive Emergency Response organization is formed under headof EOF. And MACST team supports emergency response following the order of EOF head.

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APPENDIX B – PHASE 2 RESPONSES

Diagram of organization chart for MACST teamSupplemental Files: None
Anticipated Benefits: Improvement of capability to cope with BDBA
The events described in this lesson learnt occurred: Korea, until 2020

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APPENDIX B – PHASE 2 RESPONSES

Spain

Lesson Learnt: SP-01 – Verification and Validation for Emergency Situations
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
During validations involving Emergency equipment and systems, the verification and validation[V&V] have to be done with the most conservatives scenarios expected. Even when Procedures
cannot take into account every single possible situation, Human Performance specialist need togo further and raise up those situations to evaluate responses from plant personnel.
For this reason, during Containment building venting system V&V, difficult personal situations(happening out of the plant as happened in Fukushima) were raised to Operators in the field, toanalyze their response. The principal lesson learned was that this kind of situations need to be"trained" to be prepared to them.
This practice supposed the review of the Guidance for V&V relating, overall, HU aspects as well
as taking into account other aspects such as Doses, events taking place at the same time,
unexpected situations, etc.
Supplemental Files: None
Anticipated Benefits: Preparedness for an emergency situation. Review of the V&V guidance inthe nuclear power plant.
The events described in this lesson learnt occurred: 2016
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP–02– Communication During Emergencies
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity

In the nuclear power plant case, corporate response facilities

Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification

88

Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
When analyzing the Fukushima event, in the nuclear power plant a need to keep the relativesof personnel informed (As well as to keep workers informed of how their relatives are), a
telephone line to do so was established, and a card with the telephone number was given to all"on duty" workers to give to their relatives.
Supplemental Files: None
Anticipated Benefits: This aspect could help managing the incoming calls to the plant in caseof emergency. It also would allow workers to focus on the emergency and forgetting about
having to contact their relatives.
The events described in this lesson learnt occurred: 2015
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP–03 – Magnetic Help Guides for Portable Equipment
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]

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APPENDIX B – PHASE 2 RESPONSES

Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
During the realization of the emergency portable equipment surveillance tests, it was required
to start up the portable equipment in the field. Magnetic help guides for each portableequipment were developed helping the field operator to quickly start up the portable equipment,
and also minimize any possible human error that could prevent from the start up the equipment
the first time.
Also, during an emergency situation [it] could take time to find out the procedure for using theportable equipment and the procedure takes time to be followed by the field operator. And when
the procedure is followed, the field operator needs one hand to hold the procedure, so he cannot
use both hands to work with.
Supplemental Files:

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APPENDIX B – PHASE 2 RESPONSES

Anticipated Benefits: The Magnetic help guides for each portable equipment help the field
operator to quickly start up the portable equipment, and also avoid any possible human errorthat could prevent from the startup of the equipment the first time. The Magnetic help guides
are placed in each portable equipment, so the Field operator do not have to spend time to findout the procedure for using the portable equipment. These magnetic helps could be moved andplaced next to the area where the devices (switches, valves, etc.) are manipulated, so the field
operator do not have to move to look at it and also has free hands to work with. These magnetic
helps also include pictures, so they are clear and easy to be followed so it minimizes the humanerrors.
The events described in this lesson learnt occurred: June 2016
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP–04 – Visual Aids for Identifying Emergency Equipment
Applicability
Type of Response
On-site Response(Mitigating Event)Off-site Response(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
During the realization of a Plant Drill, where the Emergency Procedure requires to identify andmanipulate emergency related equipment (valves, cabinets, Control Room Switches, etc.) in
Station Black Out situation, refractive [fluorescent] metal identification plates were developed
and refractive [fluorescent] tape was used in Control Room switches to help the field operator
and the Control Room staff to identify and manipulate emergency related equipment (valves,cabinets, Control Room Switches, etc.) in SBO situation.
Supplemental Files:

Valve refractive [fluorescent] metal identification plate

Orange refractive [fluorescent] tape used to mark cabinets

Anticipated Benefits: The refractive [fluorescent] metal identification plates help the field
operator to quickly identify and manipulate the emergency valves involved in the emergency
procedures.
The refractive [fluorescent] tape used to mark cabinets in the field plates help the field operator
to quickly identify and manipulate this equipment involved in the emergency procedures.

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The refractive [fluorescent] tape used to mark Control Room switches help the field operator toquickly identify and manipulate the emergency control room switches involved in theemergency procedures.
All of this help the Control Room Staff and the Field Operators to execute the emergency
procedures, minimizing human errors and improving performance times.
The events described in this lesson learnt occurred: April 2016
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP–05 – Training for Emergency Equipment Transport
Applicability
Type of Response
On-site Response(Mitigating Event)Off-site Response(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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Description:
Theoretical and practical training in transport means management for transfer of equipment
related to PEI [internal emergency plan] in the event of extensive damage, to the personnel ofthe electrical maintenance, instrumentation and mechanic, services section, supply
management and chemistry.
Supplemental Files: None
Anticipated Benefits: This training will guarantee a minimum of people with skills andknowledge to handle the emergency teams and following a defined planning try to minimize
human errors.
The events described in this lesson learnt occurred: February – June 2015
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP–06 – Communication System Improvements
Applicability
Type of Response
On-site Response(Mitigating Event)Off-site Response(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

94

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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APPENDIX B – PHASE 2 RESPONSES

Description:
The improvements associated with communication systems in emergency, including those ofreinforcement in situations of loss prolonged power supply
Supplemental Files: None
Anticipated Benefits: The improvement of the media ensures that there is communication at
all times including situations of major emergencies
The events described in this lesson learnt occurred: June 2014
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP-07 – Stress Management Guide and Posters
Applicability
Type of Response
On-site Response(Mitigating Event)Off-site Response(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]

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Description:
As a result of the analysis of the lessons learned from the Fukushima accident, was identified
the importance of stress management for Emergency response staff. (They continued working
on a tense environment for a long period without leaving the plant, even when some of themembers of his family were suffering due to disaster.)
In order to improve the response of the members of the emergency it has been elaborated adocument available on the Alternative Emergency Management Centre focused on stress andanxiety management techniques. Four posters showing the behavior patterns with relaxing
images, has been placed on the bedrooms and on the rest room of the Alternative Emergency
Management Centre too.
Supplemental Files:

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Anticipated Benefits: In case of situation of stress maintained by an emergency, this guide andstress management techniques can help workers to relax and rest, minimizing errors inmanagement and communication from stress and fatigue.
The events described in this lesson learnt occurred: 2018
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

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APPENDIX B – PHASE 2 RESPONSES

Lesson Learnt: SP-08 – Leadership During Emergency Situations
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
One of the lessons learned from the accident was the different treatment given to the crisis
situation at the Fukushima Daini and Onagawa plants, in relation to the adequate leadershipduring the emergency situation.
With the objective of reinforcing this aspect, has been included in the training of Emergency
response staff aid tools related to emergency leadership. Two posters have been placed on

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Alternative Emergency Management Centre (CAGE) and on the Technical Support Centre (CAT),summarizing appropriate communication practices related to this topic.
Supplemental Files:

Anticipated Benefits: Improvement leadership of emergency response staff during emergency
management.
An adequate leadership impacts not only on the decision making process, but also on theenvironment and proper management of the emergency, so these issues will be improved
through training
The events described in this lesson learnt occurred: 2018
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: SP-09 – Command and Control in Emergencies Guide
Applicability
Type of Response

100

On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

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APPENDIX B – PHASE 2 RESPONSES

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training[other]Description:
In 2014, after analyzing the results obtained from several internal and external observations,and following the process of continuous improvement within the organization, an area for
improvement in the field of emergency command and control was identified, specifically in the
management of accidents in the Technical Support Center (CAT in Spanish).
To this end, we developed a guide which includes the systematization of a series of processes
that, thanks to its simplicity, enable a fast application and facilitates the exercise of theemergency team duties.
The guide consists of seven (7) sections, and a summary, which develop those aspects to beconsidered in the event an emergency arose. These aspects are:•Priorities: any type of decision making during an emergency must take into account thefollowing priorities: the General Public, the staff, the Plant, the Environment and Safety.

•

Principles of Command and Control: the following principles are defined and established
as a reminder at the Technical Support Center:–

Anticipation: the team must anticipate possible scenarios and be prepared for what
may come.

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Communication: accurate information must be shared through the best available
channel, and the understanding of the information must be confirmed.

–

Delegation: the chief of the emergency services must delegate those activities thatmight prevent him from having a global vision of the situation, and must have themost appropriate equipment for each function.

–

Concurrent Activities: in order to optimize the timings, different actions must be run
in parallel while maintaining control of the scenario.

–

Flexibility: in an emergency situation, flexibility, common sense and skipping therules are required if it is necessary in order to solve the emergency.

–

Leadership: to maintain the situation and the decision making drive under control
until the emergency is over.

•Decision making process: this process can be summarized in the following stages:
information gathering and sharing; achievement of an even situational mindset within
the team; to reach a joint decision making and finally, to perform accordingly. This cycle
will repeat until the emergency situation is over.

•

Chain of command: the establishment of a chain of command helps to reduce steps,
connects managers and defines their responsibilities.

•

Resource management: by answering a series of questions, it helps to reflect on theavailable and necessary resources allocated to tackle and emergency in the most realistic
and effective possible way.

•

“Blackboard management”: this tool ensures an intuitive emergency monitoring andhelps to establish recovery strategies as well as the actions to be taken in each phase.

•

Briefing format: the emergency manager periodically reviews the situation; the strategies
defined; the progress and status of the actions taken, and also receives a quick feedback
from the team in order to ensure everything is properly understood.

Supplemental Files: Text of “Command and Control in Emergencies Guide” is provided on thefollowing pages.
Anticipated Benefits: The immediate benefits from the implementation of the “Command andcontrol in emergency situations” guide have resulted into a simple and, at the same time, strong
system which, in the event an emergency should arise, enables to establish priorities in thedecision making process; to have emergency related command and control basic and sharedfundamentals; to have a tool to properly manage the available resources; to improve themonitoring of strategies to follow according to the emergency status and to improve thepreparation and coordination of the Emergency team.
The events described in this lesson learnt occurred: February 2014 - 2018
Note: Text in brackets [ ] added to submittal by Task Group for clarification.
Command and Control in Emergencies Guide in pdf file:

Adobe Acrobat
PDFXML Document

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APPENDIX B – PHASE 2 RESPONSES

United States

Lesson Learnt: US-01 – Human Reliability Analysis Methods for Use of FLEX
Strategies and Equipment
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations
Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]Job categories
Control Room Operators

Emergency Operations Facility

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training

Guidance Development

This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training

Human Reliability Analysis

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Description:
Both the U.S. NRC and industry are beginning to modify PRA models to represent theimplementation of the flexible coping strategies (FLEX) and associated equipment/capabilities
that have been put in place at U.S. nuclear power plants following the accident at Fukushima
Daiichi. Some of the NRC’s Standardized Plant Analysis Risk (SPAR) models have been updated
to include FLEX strategies and some utilities have expanded their PRA models to include the useof FLEX equipment. Also, some utilities have requested licensing changes that involve using
FLEX strategies or equipment for non-FLEX contexts (e.g., provide additional diesel generator
redundancy in loss of offsite power scenarios).
The NRC has published a two-volume report that illustrates the NRC’s effort to appropriately
credit human actions within FLEX strategies using a systematic, qualitative approach to produce
human error probability (HEP) estimates. Volume 1 of this report, “Utilization of Expert
Judgment to Support Human Reliability Analysis of Flexible Coping Strategies (FLEX),” wascompleted in 2018 as an assessment of FLEX action feasibility using data collected by the NRC
staff. This information was used to inform the development of the NRC’s Integrated Human
Event Analysis System for Event and Condition Assessment (IDHEAS-ECA). IDHEAS-ECA is ahuman reliability analysis (HRA) method that can be used for FLEX and Non-FLEX actions. Uponcompletion of the method, in 2019, the NRC and industry further explored the feasibility of FLEX
actions using IDHEAS-ECA. This work is documented in Volume 2 of the report, “Flexible Coping
Strategies (FLEX) HRA Using IDHEAS-ECA.” The two reports demonstrate how the teams ofexperts were used and describe how each project was introduced into the NRC’s framework for
FLEX. Both projects capture the state of knowledge and uncertainties of the technical issues
within FLEX and non-FLEX scenarios.
Supplemental Files: None
Anticipated Benefits: Both projects described in the report serve as a bases to explore the data
and knowledge of FLEX within HRA. They demonstrate a cohesive effort to address thechallenges identified in existing HRA methods and create solutions to bridge the gaps ofunderstanding. Previous methods used by the NRC assumed that FLEX actions were not feasible.
However, these two-projects provide evidence of feasibility. Both efforts increased theunderstanding of operator actions using FLEX equipment and developed estimates of theirfeasibility to inform and improve analysis, methodologies, and quantification tools
The events described in this lesson learnt occurred: From 2018 – 2019.
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

Lesson Learnt: US-02 – FLEX Diesel Generator Experience
Applicability
Type of Response
On-site Response

Off-site Response(Mitigating Event)(Protective Actions for Public)

Plant Locations

104

Main Control RoomTechnical Support Center

Remote Shutdown Panel / Facility

Emergency Operations Facility

Other Local Control Station / Field Activity[other]

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APPENDIX B – PHASE 2 RESPONSES

Job categories
Control Room Operators

Technical Support Center

Field Operators

Other Emergency Response Organization Personnel

Maintenance Technicians

Security

Health Physicists/Radiation Protection/Chemistry[other]Time / Method of Identification
Initial Analysis / Development of the Action

Drill / Exercise

Validation

Audit / Self-Assessment

Training[other]This Lesson Learnt Concerns
Mitigation Strategies

Plant Instrumentation/Controls

Other Procedures and Guidelines

Human-system Interfaces

Staffing

Communications Equipment

Organizational Structures

Work Planning

Communication

Technical Support

Decision-making authorities

Emergency Response Facilities

Safety Culture

Emergency Response Plans

Personnel Qualifications

Extended Longer-term Response

Training

Equipment design, maintenance and testing

Description:
NRC licensees use diverse and flexible coping strategies (FLEX) equipment at nuclear power
plants to implement long-term core cooling, spent fuel cooling, and containment integrity inbeyond-design-basis event scenarios.
On September 26, 2019 and again on April 1, 2020, the licensee for the River Bend nuclear
power station conducted periodic testing of their FLEX diesel generators. In both instances,multiple FLEX diesel generators failed to operate. On July 11, 2019, the licensee for Clinton Power
Station (Clinton) discovered that the electrical phase rotation of the “A” FLEX diesel generator
was opposite to that of the load center for its in-plant loads. If the facility had used the “A” FLEX
diesel generator to power any in-plant equipment, it would have caused phase-dependent loads
to rotate backwards, potentially damaging in-plant safety-related equipment.
On September 15, 2020, the U.S. Nuclear Regulatory Commission issued Information Notice2020-02, Flex Diesel Generator Operational Challenges. The information notice (IN) informed
addressees of these recent operational challenges involving FLEX diesel generators anddescribed the deficiencies in licensee design, testing, and maintenance practices that
contributed to the failures. These deficiencies included failure to provide adequate oversight ofvendor provided maintenance and failure to test under the loading conditions that would
actually be present during a beyond-design-basis external event.
Supplemental Files: None
Anticipated Benefits: The anticipated benefit of the information notice is increased awarenessof conditions that could contribute to operational challenges with FLEX diesel generators atother nuclear facilities. The information can be evaluated for applicability at other facilities andprovide the basis for corrective action, if warranted, that can reduce the potential for similar

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APPENDIX B – PHASE 2 RESPONSES

failures. FLEX diesel generator reliability is important to successful implementation of
mitigation strategies for beyond-design-basis external events, mitigating the risk related totaking safety-related systems out of service, and to reducing a plant’s overall risk profile.
The events described in this lesson learnt occurred: September 2019 – July 2020
Note: Text in brackets [ ] added to submittal by Task Group for clarification.

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