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{{#Wiki_filter:Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov  DOE Nuclear Safety Workshop September 20, 2012 2 The Pre-PRA Era Management of (unquantified at the time) uncertainty was always a concern. Defense-in-depth and safety margins became embedded in the regulations.  -in-philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear  Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.
{{#Wiki_filter:United States Nuclear Regulatory Commission Official Hearing Exhibit In the Matter of:                    Entergy Nuclear Operations, Inc.                                 RIV000160 (Indian Point Nuclear Generating Units 2 and 3)
Evolution of PRA Development Reactor Safety Study (WASH-1400; 1975) Individual Plant Examinations (1988) NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990) Plant-specific PRAs Licensees NRC State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012) Level 3 PRA Project  3 4 Quantitative Safety Goals of the  Nuclear Regulatory Commission (August, 1986) Early and latent cancer mortality risks to an individual living near the plant should not        exceed 0.1 percent of the background accident or cancer mortality risk, approximately                    5x10-7/year for early death and                              2x10-6/year for death from cancer. The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary. The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.
ASLBP #: 07-858-03-LR-BD01                                        Date Submitted: June 9, 2015 Docket #: 05000247 l 05000286 Exhibit #: RIV000160-00-BD01                Identified: 11/5/2015 Admitted: 11/5/2015                        Withdrawn:
5  PRA Model Overview and Subsidiary Objectives PLANT MODEL CONTAINMENT MODEL SITE/CONSEQUENCE MODEL Level I Level II Level III Results Accident sequences leading to plant damage states Results Containment failure/release sequences Results Public health effects PLANT MODE At-power Operation Shutdown / Transition Evolutions SCOPE Internal Events External Events CDF 10-4/ry LERF 10-5/ry QHOs Uncertainties 6 PRA Policy Statement (1995) The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy. PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.
Rejected:                                      Stricken:
Evolution of the Risk-Informed Regulatory System Regulatory Requirements Anticipated Transients without Scram (ATWS) Station Blackout (SBO) Maintenance Rule Risk-Informed Changes to the Licensing Basis  Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69) New Reactor Licensing Reactor Oversight Process Fire Protection  7 Risk Management Task Force (RMTF) Suggested by Chairman Jaczko in late 2010 Task Force formed in February 2011 Charter 8 adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear 
Other:
-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during  Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations  NRC staff proposal to be submitted to Commission in early 2013 Fukushima Near-Term Task Force Recommendation 1 9 A Proposed Risk Management Regulatory Framework (NUREG-2150) 10 Decision-Making Process Use a disciplined process to achieve the risk management goal: Identify issue Identify Options Analyze Deliberate Implement Decision  Monitor Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to: Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and  Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Diversity of Activities 11 Operating Reactors Transportation NRC Regulated Activities Fuel Cycle Waste Disposal and Storage Materials Reactors New Reactors Generation IV Reactors Research and Test Reactors Low Level Waste High Level Waste ISFSI Uranium Recovery Operating Reactor Recommendations 12 The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA. NRC should establish via rulemaking  a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.
Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov DOE Nuclear Safety Workshop September 20, 2012
Proposed Regulatory Framework: Power Reactors 13 Design basis event? Adequate protection rule? Current cost-beneficial safety enhancement rule? Included risk-important scenario? Adequate Protection  Category Proposed Design Enhancement Category Remaining scenarios Proposed Residual Risk Category 14 Who decides what is included? NRC specifies initiators or scenarios Licensees use site-specific PRAs What criteria are used for inclusion? Initiating events with frequency greater than xx Accident sequences with frequency greater than yy Cost-beneficial rules Design Enhancement Characteristics What criteria are used for disposition? Risk less than zz ALARA Combination Proposed Design Enhancement Category Fuel Cycle Facilities  Finding F-F-1:  The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission. Finding F-F-2:  The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities. 15 Recommendation F-R-1: The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.
 
Acronyms ALARA  as low as reasonably achievable ATWS  anticipated transient without scram CDF  core damage frequency ISA  integrated safety analysis ISFSI  independent spent fuel storage installation LERF  large early release frequency NRC  Nuclear Regulatory Commission PRA  probabilistic risk assessment  QHO  quantitative health objective RMTF  Risk Management Task Force SBO  station blackout SOARCA  State-of-the-Art Reactor Consequence Analysis 16 Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov  DOE Nuclear Safety Workshop September 20, 2012 2 The Pre-PRA Era Management of (unquantified at the time) uncertainty was always a concern. Defense-in-depth and safety margins became embedded in the regulations.  -in-philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear  Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.
The Pre-PRA Era
Evolution of PRA Development Reactor Safety Study (WASH-1400; 1975) Individual Plant Examinations (1988) NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990) Plant-specific PRAs Licensees NRC State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012) Level 3 PRA Project  3 4 Quantitative Safety Goals of the  Nuclear Regulatory Commission (August, 1986) Early and latent cancer mortality risks to an individual living near the plant should not        exceed 0.1 percent of the background accident or cancer mortality risk, approximately                    5x10-7/year for early death and                              2x10-6/year for death from cancer. The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary. The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.
* Management of (unquantified at the time) uncertainty was always a concern.
5 PRA Model Overview and Subsidiary Objectives PLANT MODEL CONTAINMENT MODEL SITE/CONSEQUENCE MODEL Level I Level II Level III Results Accident sequences leading to plant damage states Results Containment failure/release sequences Results Public health effects PLANT MODE At-power Operation Shutdown / Transition Evolutions SCOPE Internal Events External Events CDF 10-4/ry LERF 10-5/ry QHOs Uncertainties 6 PRA Policy Statement (1995) The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy. PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.
* Defense-in-depth and safety margins became embedded in the regulations.
Evolution of the Risk-Informed Regulatory System Regulatory Requirements Anticipated Transients without Scram (ATWS) Station Blackout (SBO) Maintenance Rule Risk-Informed Changes to the Licensing Basis  Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69) New Reactor Licensing Reactor Oversight Process Fire Protection  7 Risk Management Task Force (RMTF) Suggested by Chairman Jaczko in late 2010 Task Force formed in February 2011 Charter 8 adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear 
* Defense-in-Depth is an element of the NRCs safety philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear facility. [Commissions White Paper, February 1999]
-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during  Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations  NRC staff proposal to be submitted to Commission in early 2013 Fukushima Near-Term Task Force Recommendation 1 9 A Proposed Risk Management Regulatory Framework (NUREG-2150) 10 Decision-Making Process Use a disciplined process to achieve the risk management goal: Identify issue Identify Options Analyze Deliberate Implement Decision  Monitor Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to: Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Diversity of Activities 11 Operating Reactors Transportation NRC Regulated Activities Fuel Cycle Waste Disposal and Storage Materials Reactors New Reactors Generation IV Reactors Research and Test Reactors Low Level Waste High Level Waste ISFSI Uranium Recovery Operating Reactor Recommendations 12 The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA. NRC should establish via rulemaking  a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.
* Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.
Proposed Regulatory Framework: Power Reactors 13 Design basis event? Adequate protection rule? Current cost-beneficial safety enhancement rule? Included risk-important scenario? Adequate Protection  Category Proposed Design Enhancement Category Remaining scenarios Proposed Residual Risk Category 14 Who decides what is included? NRC specifies initiators or scenarios Licensees use site-specific PRAs What criteria are used for inclusion? Initiating events with frequency greater than xx Accident sequences with frequency greater than yy Cost-beneficial rules Design Enhancement Characteristics What criteria are used for disposition? Risk less than zz ALARA Combination Proposed Design Enhancement Category Fuel Cycle Facilities  Finding F-F-1:  The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission. Finding F-F-2: The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities. 15 Recommendation F-R-1:  The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.
2
Acronyms ALARA as low as reasonably achievable ATWS anticipated transient without scram CDF core damage frequency ISA integrated safety analysis ISFSI independent spent fuel storage installation LERF large early release frequency NRC Nuclear Regulatory Commission PRA probabilistic risk assessment QHO quantitative health objective RMTF Risk Management Task Force SBO station blackout SOARCA State-of-the-Art Reactor Consequence Analysis 16}}
 
Evolution of PRA Development
* Reactor Safety Study (WASH-1400; 1975)
* Individual Plant Examinations (1988)
* NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990)
* Plant-specific PRAs Licensees NRC
* State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012)
* Level 3 PRA Project 3
 
Quantitative Safety Goals of the Nuclear Regulatory Commission (August, 1986)
Early and latent cancer mortality risks to an individual living near the plant should not exceed 0.1 percent of the background accident or cancer mortality risk, approximately 5x10-7/year for early death and 2x10-6/year for death from cancer.
The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary.
The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.
4
 
PRA Model Overview and Subsidiary Objectives CDF                          LERF                            QHOs 10-4/ry                      10-5/ry Level I              Level II                        Level III PLANT              CONTAINMENT                    SITE/CONSEQUENCE MODEL                  MODEL                            MODEL Results                Results                          Results Accident              Containment                      Public health sequences              failure/release                  effects leading to            sequences plant damage                                                SCOPE states                PLANT MODE                            Internal Events At-power Operation                    External Events Shutdown / Transition Evolutions Uncertainties 5
 
PRA Policy Statement (1995)
* The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy.
* PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.
6
 
Evolution of the Risk-Informed Regulatory System
* Regulatory Requirements Anticipated Transients without Scram (ATWS)
Station Blackout (SBO)
Maintenance Rule
* Risk-Informed Changes to the Licensing Basis Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69)
* New Reactor Licensing
* Reactor Oversight Process
* Fire Protection 7
 
Risk Management Task Force (RMTF)
* Suggested by Chairman Jaczko in late 2010
* Task Force formed in February 2011
* Charter To develop a strategic vision and options for adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear material.
8
 
Fukushima Near-Term Task Force Recommendation 1
* This regulatory approach, established and supplemented piece-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during NRC technical review and inspection.
* Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations
* NRC staff proposal to be submitted to Commission in early 2013 9
 
A Proposed Risk Management Regulatory Framework (NUREG-2150)
Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to:
Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Decision-Making Process Use a disciplined process to achieve the risk management goal:
Identify Identify issue                                            Analyze Options Implement Monitor                                              Deliberate Decision 10
 
Diversity of Activities NRC Regulated Activities Waste Disposal Reactors    Materials                              Fuel Cycle Transportation and Storage Operating Low Level Waste Reactors New Reactors                        High Level Waste Generation IV ISFSI Reactors Research and                            Uranium Test Reactors                          Recovery 11
 
Operating Reactor Recommendations The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA.
NRC should establish via rulemaking a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.
12
 
Proposed Regulatory Framework: Power Reactors Design basis event?
Adequate Adequate protection rule?            Protection Category Current cost-beneficial safety enhancement rule?
Proposed Included risk-         Design important scenario?
Enhancement Category Remaining scenarios Proposed Residual Risk Category 13
 
Design Enhancement Characteristics Who decides what is included?
* NRC specifies initiators or scenarios
* Licensees use site-specific PRAs What criteria are used for inclusion?
Proposed
* Initiating events with frequency greater than Design          xx Enhancement
* Accident sequences with frequency greater than yy Category
* Cost-beneficial rules What criteria are used for disposition?
* Risk less than zz
* ALARA
* Combination 14
 
Fuel Cycle Facilities Finding F-F-1: The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission.
Finding F-F-2: The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities.
Recommendation F-R-1: The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.
15
 
Acronyms
* ALARA - as low as reasonably achievable
* ATWS - anticipated transient without scram
* CDF - core damage frequency
* ISA - integrated safety analysis
* ISFSI - independent spent fuel storage installation
* LERF - large early release frequency
* NRC - Nuclear Regulatory Commission
* PRA - probabilistic risk assessment
* QHO - quantitative health objective
* RMTF - Risk Management Task Force
* SBO - station blackout
* SOARCA - State-of-the-Art Reactor Consequence Analysis 16
 
United States Nuclear Regulatory Commission Official Hearing Exhibit In the Matter of:                    Entergy Nuclear Operations, Inc.                                RIV000160 (Indian Point Nuclear Generating Units 2 and 3)
ASLBP #: 07-858-03-LR-BD01                                        Date Submitted: June 9, 2015 Docket #: 05000247 l 05000286 Exhibit #: RIV000160-00-BD01                Identified: 11/5/2015 Admitted: 11/5/2015                        Withdrawn:
Rejected:                                      Stricken:
Other:
Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov DOE Nuclear Safety Workshop September 20, 2012
 
The Pre-PRA Era
* Management of (unquantified at the time) uncertainty was always a concern.
* Defense-in-depth and safety margins became embedded in the regulations.
* Defense-in-Depth is an element of the NRCs safety philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear facility. [Commissions White Paper, February 1999]
* Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.
2
 
Evolution of PRA Development
* Reactor Safety Study (WASH-1400; 1975)
* Individual Plant Examinations (1988)
* NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990)
* Plant-specific PRAs Licensees NRC
* State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012)
* Level 3 PRA Project 3
 
Quantitative Safety Goals of the Nuclear Regulatory Commission (August, 1986)
Early and latent cancer mortality risks to an individual living near the plant should not exceed 0.1 percent of the background accident or cancer mortality risk, approximately 5x10-7/year for early death and 2x10-6/year for death from cancer.
The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary.
The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.
4
 
PRA Model Overview and Subsidiary Objectives CDF                          LERF                            QHOs 10-4/ry                      10-5/ry Level I              Level II                        Level III PLANT              CONTAINMENT                    SITE/CONSEQUENCE MODEL                  MODEL                            MODEL Results                Results                          Results Accident              Containment                      Public health sequences              failure/release                  effects leading to             sequences plant damage                                                SCOPE states                PLANT MODE                            Internal Events At-power Operation                    External Events Shutdown / Transition Evolutions Uncertainties 5
 
PRA Policy Statement (1995)
* The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy.
* PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.
6
 
Evolution of the Risk-Informed Regulatory System
* Regulatory Requirements Anticipated Transients without Scram (ATWS)
Station Blackout (SBO)
Maintenance Rule
* Risk-Informed Changes to the Licensing Basis Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69)
* New Reactor Licensing
* Reactor Oversight Process
* Fire Protection 7
 
Risk Management Task Force (RMTF)
* Suggested by Chairman Jaczko in late 2010
* Task Force formed in February 2011
* Charter To develop a strategic vision and options for adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear material.
8
 
Fukushima Near-Term Task Force Recommendation 1
* This regulatory approach, established and supplemented piece-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during NRC technical review and inspection.
* Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations
* NRC staff proposal to be submitted to Commission in early 2013 9
 
A Proposed Risk Management Regulatory Framework (NUREG-2150)
Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to:
Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Decision-Making Process Use a disciplined process to achieve the risk management goal:
Identify Identify issue                                            Analyze Options Implement Monitor                                              Deliberate Decision 10
 
Diversity of Activities NRC Regulated Activities Waste Disposal Reactors    Materials                              Fuel Cycle Transportation and Storage Operating Low Level Waste Reactors New Reactors                        High Level Waste Generation IV ISFSI Reactors Research and                            Uranium Test Reactors                          Recovery 11
 
Operating Reactor Recommendations The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA.
NRC should establish via rulemaking a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.
12
 
Proposed Regulatory Framework: Power Reactors Design basis event?
Adequate Adequate protection rule?            Protection Category Current cost-beneficial safety enhancement rule?
Proposed Included risk-        Design important scenario?
Enhancement Category Remaining scenarios Proposed Residual Risk Category 13
 
Design Enhancement Characteristics Who decides what is included?
* NRC specifies initiators or scenarios
* Licensees use site-specific PRAs What criteria are used for inclusion?
Proposed
* Initiating events with frequency greater than Design          xx Enhancement
* Accident sequences with frequency greater than yy Category
* Cost-beneficial rules What criteria are used for disposition?
* Risk less than zz
* ALARA
* Combination 14
 
Fuel Cycle Facilities Finding F-F-1: The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission.
Finding F-F-2: The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities.
Recommendation F-R-1: The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.
15
 
Acronyms
* ALARA - as low as reasonably achievable
* ATWS - anticipated transient without scram
* CDF - core damage frequency
* ISA - integrated safety analysis
* ISFSI - independent spent fuel storage installation
* LERF - large early release frequency
* NRC - Nuclear Regulatory Commission
* PRA - probabilistic risk assessment
* QHO - quantitative health objective
* RMTF - Risk Management Task Force
* SBO - station blackout
* SOARCA - State-of-the-Art Reactor Consequence Analysis 16}}

Latest revision as of 03:59, 31 October 2019

Official Exhibit - RIV000160-00-BD01 - U.S. NRC, Commissioner Apostolakis, Application of Risk Assessment and Management to Nuclear Safety (DOE Nuclear Safety Workshop, Sept. 2012), Available at, http://energy.gov/sites/prod/files/2013/12/f
ML15334A211
Person / Time
Site: Indian Point  Entergy icon.png
Issue date: 06/09/2015
From:
Riverkeeper
To:
Atomic Safety and Licensing Board Panel
SECY RAS
References
RAS 27920, ASLBP 07-858-03-LR-BD01, 50-247-LR, 50-286-LR
Download: ML15334A211 (16)
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Text

United States Nuclear Regulatory Commission Official Hearing Exhibit In the Matter of: Entergy Nuclear Operations, Inc. RIV000160 (Indian Point Nuclear Generating Units 2 and 3)

ASLBP #: 07-858-03-LR-BD01 Date Submitted: June 9, 2015 Docket #: 05000247 l 05000286 Exhibit #: RIV000160-00-BD01 Identified: 11/5/2015 Admitted: 11/5/2015 Withdrawn:

Rejected: Stricken:

Other:

Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov DOE Nuclear Safety Workshop September 20, 2012

The Pre-PRA Era

  • Management of (unquantified at the time) uncertainty was always a concern.
  • Defense-in-depth and safety margins became embedded in the regulations.
  • Defense-in-Depth is an element of the NRCs safety philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear facility. [Commissions White Paper, February 1999]
  • Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.

2

Evolution of PRA Development

  • Reactor Safety Study (WASH-1400; 1975)
  • Individual Plant Examinations (1988)
  • NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990)
  • Plant-specific PRAs Licensees NRC
  • State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012)
  • Level 3 PRA Project 3

Quantitative Safety Goals of the Nuclear Regulatory Commission (August, 1986)

Early and latent cancer mortality risks to an individual living near the plant should not exceed 0.1 percent of the background accident or cancer mortality risk, approximately 5x10-7/year for early death and 2x10-6/year for death from cancer.

The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary.

The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.

4

PRA Model Overview and Subsidiary Objectives CDF LERF QHOs 10-4/ry 10-5/ry Level I Level II Level III PLANT CONTAINMENT SITE/CONSEQUENCE MODEL MODEL MODEL Results Results Results Accident Containment Public health sequences failure/release effects leading to sequences plant damage SCOPE states PLANT MODE Internal Events At-power Operation External Events Shutdown / Transition Evolutions Uncertainties 5

PRA Policy Statement (1995)

  • The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy.
  • PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.

6

Evolution of the Risk-Informed Regulatory System

Station Blackout (SBO)

Maintenance Rule

  • Risk-Informed Changes to the Licensing Basis Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69)
  • New Reactor Licensing
  • Reactor Oversight Process
  • Fire Protection 7

Risk Management Task Force (RMTF)

  • Suggested by Chairman Jaczko in late 2010
  • Task Force formed in February 2011
  • Charter To develop a strategic vision and options for adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear material.

8

Fukushima Near-Term Task Force Recommendation 1

  • This regulatory approach, established and supplemented piece-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during NRC technical review and inspection.
  • Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations
  • NRC staff proposal to be submitted to Commission in early 2013 9

A Proposed Risk Management Regulatory Framework (NUREG-2150)

Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to:

Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Decision-Making Process Use a disciplined process to achieve the risk management goal:

Identify Identify issue Analyze Options Implement Monitor Deliberate Decision 10

Diversity of Activities NRC Regulated Activities Waste Disposal Reactors Materials Fuel Cycle Transportation and Storage Operating Low Level Waste Reactors New Reactors High Level Waste Generation IV ISFSI Reactors Research and Uranium Test Reactors Recovery 11

Operating Reactor Recommendations The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA.

NRC should establish via rulemaking a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.

12

Proposed Regulatory Framework: Power Reactors Design basis event?

Adequate Adequate protection rule? Protection Category Current cost-beneficial safety enhancement rule?

Proposed Included risk- Design important scenario?

Enhancement Category Remaining scenarios Proposed Residual Risk Category 13

Design Enhancement Characteristics Who decides what is included?

  • NRC specifies initiators or scenarios
  • Licensees use site-specific PRAs What criteria are used for inclusion?

Proposed

  • Accident sequences with frequency greater than yy Category
  • Cost-beneficial rules What criteria are used for disposition?
  • Risk less than zz
  • Combination 14

Fuel Cycle Facilities Finding F-F-1: The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission.

Finding F-F-2: The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities.

Recommendation F-R-1: The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.

15

Acronyms

  • ALARA - as low as reasonably achievable
  • CDF - core damage frequency
  • ISA - integrated safety analysis
  • ISFSI - independent spent fuel storage installation
  • NRC - Nuclear Regulatory Commission
  • QHO - quantitative health objective
  • RMTF - Risk Management Task Force
  • SBO - station blackout
  • SOARCA - State-of-the-Art Reactor Consequence Analysis 16

United States Nuclear Regulatory Commission Official Hearing Exhibit In the Matter of: Entergy Nuclear Operations, Inc. RIV000160 (Indian Point Nuclear Generating Units 2 and 3)

ASLBP #: 07-858-03-LR-BD01 Date Submitted: June 9, 2015 Docket #: 05000247 l 05000286 Exhibit #: RIV000160-00-BD01 Identified: 11/5/2015 Admitted: 11/5/2015 Withdrawn:

Rejected: Stricken:

Other:

Application of Risk Assessment and Management to Nuclear Safety George Apostolakis Commissioner US Nuclear Regulatory Commission CmrApostolakis@nrc.gov DOE Nuclear Safety Workshop September 20, 2012

The Pre-PRA Era

  • Management of (unquantified at the time) uncertainty was always a concern.
  • Defense-in-depth and safety margins became embedded in the regulations.
  • Defense-in-Depth is an element of the NRCs safety philosophy that employs successive compensatory measures to prevent accidents or mitigate damage if a malfunction, accident, or naturally caused event occurs at a nuclear facility. [Commissions White Paper, February 1999]
  • Design Basis Accidents are postulated accidents that a nuclear facility must be designed and built to withstand without loss to the systems, structures, and components necessary to assure public health and safety.

2

Evolution of PRA Development

  • Reactor Safety Study (WASH-1400; 1975)
  • Individual Plant Examinations (1988)
  • NUREG-1150 (Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants, 1990)
  • Plant-specific PRAs Licensees NRC
  • State-of-the-Art Reactor Consequence Analyses (SOARCA, 2012)
  • Level 3 PRA Project 3

Quantitative Safety Goals of the Nuclear Regulatory Commission (August, 1986)

Early and latent cancer mortality risks to an individual living near the plant should not exceed 0.1 percent of the background accident or cancer mortality risk, approximately 5x10-7/year for early death and 2x10-6/year for death from cancer.

The prompt fatality goal applies to an average individual living in the region between the site boundary and 1 mile beyond this boundary.

The latent cancer fatality goal applies to an average individual living in the region between the site boundary and 10 miles beyond this boundary.

4

PRA Model Overview and Subsidiary Objectives CDF LERF QHOs 10-4/ry 10-5/ry Level I Level II Level III PLANT CONTAINMENT SITE/CONSEQUENCE MODEL MODEL MODEL Results Results Results Accident Containment Public health sequences failure/release effects leading to sequences plant damage SCOPE states PLANT MODE Internal Events At-power Operation External Events Shutdown / Transition Evolutions Uncertainties 5

PRA Policy Statement (1995)

  • The use of PRA should be increased to the extent supported by the state of the art and data and in a manner that complements the defense-in-depth philosophy.
  • PRA should be used to reduce unnecessary conservatisms associated with current regulatory requirements.

6

Evolution of the Risk-Informed Regulatory System

Station Blackout (SBO)

Maintenance Rule

  • Risk-Informed Changes to the Licensing Basis Regulatory Guide 1.174 Technical Specification Improvement Initiatives Risk-Informed In-Service Inspection Special Treatment/Categorization Pilot (10 CFR 50.69)
  • New Reactor Licensing
  • Reactor Oversight Process
  • Fire Protection 7

Risk Management Task Force (RMTF)

  • Suggested by Chairman Jaczko in late 2010
  • Task Force formed in February 2011
  • Charter To develop a strategic vision and options for adopting a more comprehensive and holistic risk-informed, performance-based regulatory approach for reactors, materials, waste, fuel cycle, and transportation that would continue to ensure the safe and secure use of nuclear material.

8

Fukushima Near-Term Task Force Recommendation 1

  • This regulatory approach, established and supplemented piece-by-piece over the decades, has addressed many safety concerns and issues, using the best information and techniques available at the time. The result is a patchwork of regulatory requirements and other safety initiatives, all important, but not all given equivalent consideration and treatment by licensees or during NRC technical review and inspection.
  • Recommendation: Establish a logical, systematic, and coherent regulatory framework for adequate protection that appropriately balances defense in depth and risk considerations
  • NRC staff proposal to be submitted to Commission in early 2013 9

A Proposed Risk Management Regulatory Framework (NUREG-2150)

Mission Ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment Objective Manage the risks from the use of byproduct, source and special nuclear materials through appropriate performance-based regulatory controls and oversight Risk Management Goal Provide risk-informed and performance-based defense-in-depth protections to:

Ensure appropriate barriers, controls, and personnel to prevent, contain, and mitigate exposure to radioactive material according to the hazard present, the relevant scenarios, and the associated uncertainties; and Ensure that the risks resulting from the failure of some or all of the established barriers and controls, including human errors, are maintained acceptably low Decision-Making Process Use a disciplined process to achieve the risk management goal:

Identify Identify issue Analyze Options Implement Monitor Deliberate Decision 10

Diversity of Activities NRC Regulated Activities Waste Disposal Reactors Materials Fuel Cycle Transportation and Storage Operating Low Level Waste Reactors New Reactors High Level Waste Generation IV ISFSI Reactors Research and Uranium Test Reactors Recovery 11

Operating Reactor Recommendations The set of design basis events/accidents should be reviewed and revised, as appropriate, to integrate insights from the power reactor operating history and more modern methods such as PRA.

NRC should establish via rulemaking a design enhancement category of regulatory treatment for beyond-design-basis accidents. This category should use risk as a safety measure, be performance-based (including the provision for periodic updates), include consideration of costs, and be implemented on a site-specific basis.

12

Proposed Regulatory Framework: Power Reactors Design basis event?

Adequate Adequate protection rule? Protection Category Current cost-beneficial safety enhancement rule?

Proposed Included risk- Design important scenario?

Enhancement Category Remaining scenarios Proposed Residual Risk Category 13

Design Enhancement Characteristics Who decides what is included?

  • NRC specifies initiators or scenarios
  • Licensees use site-specific PRAs What criteria are used for inclusion?

Proposed

  • Accident sequences with frequency greater than yy Category
  • Cost-beneficial rules What criteria are used for disposition?
  • Risk less than zz
  • Combination 14

Fuel Cycle Facilities Finding F-F-1: The current fuel cycle regulatory approach incorporates several elements of the proposed risk management regulatory framework, such as the use of ISAs to identify safety significant items, and the implementation of a revised fuel cycle oversight program as directed by the Commission.

Finding F-F-2: The concept of defense in depth, as embedded in fuel cycle regulatory requirements and practices, is consistent with Commission guidance. Its implementation changes as the processes change at the fuel cycle facilities.

Recommendation F-R-1: The fuel cycle regulatory program should continue to evaluate the risk and the associated defense-in-depth protection by using insights gained from ISAs. ISAs should continue to evolve to support regulatory decisionmaking.

15

Acronyms

  • ALARA - as low as reasonably achievable
  • CDF - core damage frequency
  • ISA - integrated safety analysis
  • ISFSI - independent spent fuel storage installation
  • NRC - Nuclear Regulatory Commission
  • QHO - quantitative health objective
  • RMTF - Risk Management Task Force
  • SBO - station blackout
  • SOARCA - State-of-the-Art Reactor Consequence Analysis 16
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