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{{#Wiki_filter:Risk-Informed Technical Specification Initiative 4b: Risk | {{#Wiki_filter:Risk-Informed Technical Specification Initiative 4b: Risk-Informed Completion Times Brandon Hartle, Reliability and Risk Analyst Jonathan Evans, Reliability and Risk Analyst PRA Licensing Branch A, Division of Risk Assessment, NRR NEI Lessons-Learned Workshop, January 30 - 31, 2019 | ||
-Informed Completion | |||
-Learned Workshop, January 30 | Executive Summary | ||
-31, 2019 Executive Summary | * TSTF-505 and 4b LARs require the highest quality submittals | ||
*TSTF-505 and 4b LARs require the highest quality submittals | * TSTF-505 Rev. 1 suspended November 2016 | ||
*TSTF-505 Rev. 1 suspended November 2016 *3 plant-specific 4b LARs in house; 3 SEs issued | * 3 plant-specific 4b LARs in house; 3 SEs issued | ||
*NRC SE for TSTF | * NRC SE for TSTF-505 Rev. 2 issued November 2018 | ||
-505 Rev. 2 issued November 2018-Revision resolves issues, except Loss of Function Conditions | - Revision resolves issues, except Loss of Function Conditions | ||
*3 LARs in house for TSTF | * 3 LARs in house for TSTF-505 Rev. 2 2 | ||
-505 Rev. 2 2 | |||
Initiative 4b Overview | Initiative 4b Overview | ||
*Risk-Informed process to extend TS CTs based on plant configuration | * Risk-Informed process to extend TS CTs based on plant configuration | ||
*Risk evaluation using current configuration to calculate a specific CT called Risk | * Risk evaluation using current configuration to calculate a specific CT called Risk-informed Completion Time (RICT) | ||
-informed Completion Time (RICT) | * Frontstop = existing TS CT | ||
*Frontstop= existing TS CT | * Backstop = 30 day maximum | ||
*Backstop = 30 day maximum | * Applies to planned and emergent conditions 3 | ||
*Applies to planned and emergent conditions 3 | |||
Initiative 4b Overview | Initiative 4b Overview | ||
*NEI 06-09 Rev. 0 | * NEI 06-09 Rev. 0 | ||
-Introduced term | - Introduced term PRA Functional as an alternative to Operable and allowed a RICT for all PRA Functional configurations | ||
-This replaces design basis analysis requirements with PRA success criteria in the TSs*NRC SE on NEI 06 Restricted definition of | - This replaces design basis analysis requirements with PRA success criteria in the TSs | ||
Attributes of a RICT Program*Integrates Plant Risk | * NRC SE on NEI 06-09 | ||
-Manage multiple SSC outages | - Restricted definition of PRA Functional as capable of meeting design basis analysis requirements or appropriate disposition or programmatic restriction will be provided | ||
-Manage broader scope of SSCs (TS and non | - A RICT can only apply to (restorative) TS Required Actions that are not Mode changes or unit shutdown 4 | ||
-TS)*Flexible Configuration Management | |||
-Decisions include real | Attributes of a RICT Program | ||
-time risk insights | * Integrates Plant Risk | ||
-Focus on repair, not necessarily shutdown | - Manage multiple SSC outages | ||
-Emergent problems | - Manage broader scope of SSCs (TS and non-TS) | ||
*Ongoing/continuous risk awareness 5 | * Flexible Configuration Management | ||
Description of TSTF | - Decisions include real-time risk insights | ||
-505 Rev. 1 | - Focus on repair, not necessarily shutdown | ||
*Defined Conditions, Required Actions, and CTs within scope*Added new Conditions, Required Actions, and CTs to replace TS 3.0.3 and mode change conditions | - Emergent problems | ||
*Added a new program in TS Chapter 5, "Administrative Controls," entitled the "Risk | * Ongoing/continuous risk awareness 5 | ||
-Informed Completion Time Program." *Provided additional clarity for RICT entry using PRA Functional to extend CT for loss of function (LOF) mode change conditions (e.g., 3.0.3 conditions) 6 Early Challenges for TSTF-505 Rev. 1* | |||
-going in 2016 | Description of TSTF-505 Rev. 1 | ||
*5 other TSTF | * Defined Conditions, Required Actions, and CTs within scope | ||
-505 reviews submitted before pilot completed*Discrepancies between NEI 06 | * Added new Conditions, Required Actions, and CTs to replace TS 3.0.3 and mode change conditions | ||
-09 and TSTF | * Added a new program in TS Chapter 5, "Administrative Controls," entitled the "Risk-Informed Completion Time Program." | ||
-505 Rev. 1 were discovered during these integrated reviews | * Provided additional clarity for RICT entry using PRA Functional to extend CT for loss of function (LOF) mode change conditions (e.g., 3.0.3 conditions) 6 | ||
*Implementation of the TSTF in these LARs would have resulted in indeterminate and potentially substantive reduction in safety margin | |||
-505 Rev. 1 | Early Challenges for TSTF-505 Rev. 1 | ||
*Included changes to the Technical Specifications beyond scope of NRC SE on NEI 06-09-Included PRA Functional to extend CT for configurations with loss of capability to achieve design basis success criteria-Added new TS 3.0.3 Conditions and Required Actions to replace default TS 3.0.3 entry and included PRA Functional to extend CTs in the new TS-Included (in model TSTF | * Vogtle pilot 4b review on-going in 2016 | ||
-505 SE) justification for adequate defense | * 5 other TSTF-505 reviews submitted before pilot completed | ||
-in-depth and safety margin which relied on assuming | * Discrepancies between NEI 06-09 and TSTF-505 Rev. 1 were discovered during these integrated reviews | ||
*NRC staff suspended approval of TSTF | * Implementation of the TSTF in these LARs would have resulted in indeterminate and potentially substantive reduction in safety margin 7 | ||
-505, Rev.1, explaining concerns identified during review of plant | |||
-specific LARs:-Definition of PRA Functional | Issues With TSTF-505 Rev. 1 | ||
*SE on NEI 06 | * Included changes to the Technical Specifications beyond scope of NRC SE on NEI 06-09 | ||
-09 limited use of PRA Functionality by requiring | - Included PRA Functional to extend CT for configurations with loss of capability to achieve design basis success criteria | ||
-TS Conditions Involving Mode Changes or Unit Shutdowns | - Added new TS 3.0.3 Conditions and Required Actions to replace default TS 3.0.3 entry and included PRA Functional to extend CTs in the new TS | ||
*SE on NEI 06 | - Included (in model TSTF-505 SE) justification for adequate defense-in-depth and safety margin which relied on assuming NRCs restricted definition of PRA Functional, without additional disposition or programmatic restrictions for TS 3.0.3 and mode change CTs 8 | ||
-09 | |||
TSTF-505 Rev. 1 Suspension | |||
-09 1 0 TSTF-505 Rev. 2 1 1 TSTF-505 Rev. 2 Changes*Removed Loss of Function Conditions | * NRC staff suspended approval of TSTF -505, Rev.1, explaining concerns identified during review of plant-specific LARs: | ||
-Staff concerned with maintaining adequate defense in depth and safety margins | - Definition of PRA Functional | ||
-The conditions in Table 1 require additional justification that those are not Loss of Function*Newly Developed PRA Method Administrative Control Constraint | * SE on NEI 06-09 limited use of PRA Functionality by requiring remaining performance capability to meet design basis analysis requirements (e.g., maintain functional capability to perform at level of one operation train) | ||
*Conditions not modeled in the PRA are in scope | - TS Conditions Involving Mode Changes or Unit Shutdowns | ||
-Can be plant specific, PRA model dependent | * SE on NEI 06-09 a RICT can only apply to (restorative) TS Required Actions that are not Mode changes or unit shutdown 9 | ||
-Table 1 in Model application requires additional justification 1 2 TSTF-505 Rev. 2 Changes*Common Cause Failures (CCF) | |||
-Included in the TS Admin Section to address emergent failures-CCF PRA Modeling to be handled on a plant specific basis | TSTF-505 Rev. 1 Condition B does not meet design basis analysis requirements, therefore, would not meet intent of SE for NEI 06-09 1 | ||
*All hazards require technically adequate dispositions | 0 | ||
-External hazards need to be systematically considered | |||
-Addressing only the impact on baseline risk is insufficient | TSTF-505 Rev. 2 1 | ||
-Impact on configuration specific change in risk should be addressed 1 3 Initiative 4b Loss of Function Considerations | 1 | ||
*4b allows the use of PRA Functional and calculation of RICT when all trains are Inoperable | |||
-But available equipment can provide design basis success parameters upon demand OR-Define and justify adequate defense in depth and safety margins when available equipment can only provide PRA success parameters | TSTF-505 Rev. 2 Changes | ||
*Change in Backstop for CT upon Inoperability of all trains from 30 days to 24 hours-Consistent with approved and used TSTF | * Removed Loss of Function Conditions | ||
-426 which allows a maximum of 24 hours when all trains are Inoperable 1 4 | - Staff concerned with maintaining adequate defense in depth and safety margins | ||
- The conditions in Table 1 require additional justification that those are not Loss of Function | |||
*May deviate by requesting TS changes for Inoperability of all trains using PRA Functional with supporting information | * Newly Developed PRA Method Administrative Control Constraint | ||
-This review may be complex and resource intensive | * Conditions not modeled in the PRA are in scope | ||
-Suggest only using on a limited basis 1 5 | - Can be plant specific, PRA model dependent | ||
*Scope, level of detail, and technical adequacy of PRA are to be commensurate with application | - Table 1 in Model application requires additional justification 1 | ||
*Compare total CDF and LERF against RG 1.174 acceptance guidelines | 2 | ||
-Requires confidence in plant specific PRA models | |||
*Up-to-date full-scope PRA peer reviews-Supporting Requirements assessed to Capability Category II for all PRA hazards | TSTF-505 Rev. 2 Changes | ||
*Facts and Observations (F&Os) resolved or dispositioned prior to LAR submittal*Deviations from NRC accepted guidance and pilot applications add to review time and resources 1 7 4b Application Review Best Practices*Pre-submittal meetings | * Common Cause Failures (CCF) | ||
-Familiarizes staff with | - Included in the TS Admin Section to address emergent failures | ||
-Allows for clarifications to reduce acceptance review pitfalls*Reviewing recent submittals | - CCF PRA Modeling to be handled on a plant specific basis | ||
-Helps licensee anticipate and address common RAIs | * All hazards require technically adequate dispositions | ||
-Minimizes deviations from acceptable approaches/templates | - External hazards need to be systematically considered | ||
*F&O Closure Observations | - Addressing only the impact on baseline risk is insufficient | ||
*Audits-Assists with NRC review of complex 4b applications | - Impact on configuration specific change in risk should be addressed 1 | ||
-Clarifies information in the LAR to reduce RAIs 1 8 Conclusions | 3 | ||
*NRC SE for TSTF | |||
-505 Rev. 2 issued November 21, 2018 | Initiative 4b Loss of Function Considerations | ||
-Revision resolves issues, except for loss of function conditions | * 4b allows the use of PRA Functional and calculation of RICT when all trains are Inoperable | ||
-3 Initiative 4b LARS in house; 3 SEs issued | - But available equipment can provide design basis success parameters upon demand OR | ||
-3 LARs in house for TSTF | - Define and justify adequate defense in depth and safety margins when available equipment can only provide PRA success parameters | ||
-505 Rev. 2 | * Change in Backstop for CT upon Inoperability of all trains from 30 days to 24 hours | ||
*TSTF-505 and 4b LARs require the highest quality submittals | - Consistent with approved and used TSTF-426 which allows a maximum of 24 hours when all trains are Inoperable 1 | ||
-Complex reviews that rely on the technical adequacy of the PRA | 4 | ||
-High quality submittals needed to support efficient review by the NRC*Progress/Path forward | |||
-With issuance of the SE for TSTF | Initiative 4b Loss of Function Considerations | ||
-505 Rev. 2, we expect a large number of submittals in 2019 | * Using design basis success criteria for PRA Functional for loss of all trains alleviates need for justifying PRA success criteria, i.e., | ||
-Reviewing previous submittals and using best practices will facilitate efficient NRC review 1 9 List of Acronyms | - Use only SSCs relied on in the original TS specified safety function | ||
*CC -Capability Category | - Ensure design basis success criteria for parameters are met for all design basis initiators | ||
*CCF -Common Cause Failure | * May deviate by requesting TS changes for Inoperability of all trains using PRA Functional with supporting information | ||
*CDF -Core Damage Frequency | - This review may be complex and resource intensive | ||
*CT -Completion Time | - Suggest only using on a limited basis 1 | ||
*F&O -Facts and Observations | 5 | ||
*LAR -License Amendment Request | |||
*LERF -Large Early Release Frequency | TSTF-505 and 4b LAR Content 4b, Risk-Informed Completion Times | ||
*NRC -Nuclear Regulatory Commission | * Greater reliance NFPA-805, Risk-Informed on PRA Required Fire Protection scope, level of detail, | ||
*PRA -Probabilistic Risk Assessment | * More flexibility for technical 50.69 SSC Categorization licensee robustness, and plant representation 5b, Risk-Informed | ||
*RAI -Request for Additional Information | * More complex staff Surveillance Frequencies review Risk-Informed Inservice Inspection 1 | ||
*RICT -Risk Informed Completion Time | 6 | ||
*SE -Safety Evaluation | |||
*SR -Supporting Requirement | TSTF-505 and 4b LAR Content | ||
*SSC -Systems, Structures, and Components | * Scope, level of detail, and technical adequacy of PRA are to be commensurate with application | ||
*TS -Technical Specification | * Compare total CDF and LERF against RG 1.174 acceptance guidelines | ||
*TSTF -Technical Specifications Task Force 2 0 References | - Requires confidence in plant specific PRA models | ||
*TSTF-505, Revision 1, | * Up-to-date full-scope PRA peer reviews | ||
-Informed Extended Completion Times | - Supporting Requirements assessed to Capability Category II for all PRA hazards | ||
-RITSTF Initiative 4b, | * Facts and Observations (F&Os) resolved or dispositioned prior to LAR submittal | ||
).*Draft Revised Model Safety Evaluation of TSTF | * Deviations from NRC accepted guidance and pilot applications add to review time and resources 1 7 | ||
-505, Revision 2, | |||
-RITSTF Initiative 4b, | 4b Application Review Best Practices | ||
*Letter from Timothy J. McGinty, U.S. Nuclear Regulatory Commission, to Technical Specifications Task Force, | * Pre-submittal meetings | ||
-505, Revision 1, | - Familiarizes staff with licensees strategy and goals | ||
-Informed Extended Completion Times | - Allows for clarifications to reduce acceptance review pitfalls | ||
-RITSTF Initiative 4B, | * Reviewing recent submittals | ||
).*Final Safety Evaluation For Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06 09, | - Helps licensee anticipate and address common RAIs | ||
-Informed Technical Specifications Initiative 4b, Risk | - Minimizes deviations from acceptable approaches/templates | ||
-Managed Technical Specifications (RMTS) Guidelines, | * F&O Closure Observations | ||
).2 1 References | * Audits | ||
*Topical Report NEI 06 | - Assists with NRC review of complex 4b applications | ||
-09, Revision 0 | - Clarifies information in the LAR to reduce RAIs 1 | ||
-A, | 8 | ||
-Managed Technical Specifications (RMTS) Guidelines, | |||
).*Regulatory Guide 1.174, Revision 3, | Conclusions | ||
-Informed Decisions on Plant | * NRC SE for TSTF-505 Rev. 2 issued November 21, 2018 | ||
-Specific Changes to the Licensing Basis, | - Revision resolves issues, except for loss of function conditions | ||
- 3 Initiative 4b LARS in house; 3 SEs issued | |||
- 3 LARs in house for TSTF-505 Rev. 2 | |||
* TSTF-505 and 4b LARs require the highest quality submittals | |||
- Complex reviews that rely on the technical adequacy of the PRA | |||
- High quality submittals needed to support efficient review by the NRC | |||
* Progress/Path forward | |||
- With issuance of the SE for TSTF-505 Rev. 2, we expect a large number of submittals in 2019 | |||
- Reviewing previous submittals and using best practices will facilitate efficient NRC review 1 | |||
9 | |||
List of Acronyms | |||
* CC - Capability Category | |||
* CCF - Common Cause Failure | |||
* CDF - Core Damage Frequency | |||
* CT - Completion Time | |||
* F&O - Facts and Observations | |||
* LAR - License Amendment Request | |||
* LERF - Large Early Release Frequency | |||
* NRC - Nuclear Regulatory Commission | |||
* PRA - Probabilistic Risk Assessment | |||
* RAI - Request for Additional Information | |||
* RICT - Risk Informed Completion Time | |||
* SE - Safety Evaluation | |||
* SR - Supporting Requirement | |||
* SSC - Systems, Structures, and Components | |||
* TS - Technical Specification | |||
* TSTF - Technical Specifications Task Force 2 0 | |||
References | |||
* TSTF-505, Revision 1, Provide Risk-Informed Extended Completion Times | |||
- RITSTF Initiative 4b, June 14, 2011, and Model Application dated January 31, 2012 (ADAMS Accession No. ML120330410). | |||
* Draft Revised Model Safety Evaluation of TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b, May 1, 2018 (ADAMS Accession No. ML17290A005). | |||
* Letter from Timothy J. McGinty, U.S. Nuclear Regulatory Commission, to Technical Specifications Task Force, Issues With Technical Specifications Task Force Traveler TSTF-505, Revision 1, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4B, dated November 15, 2016 (ADAMS Accession No. ML16281A021). | |||
* Final Safety Evaluation For Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06 09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines, May 17, 2007 (ADAMS Accession No. ML071200238). 2 1 | |||
References | |||
* Topical Report NEI 06-09, Revision 0-A, Risk-Informed Technical Specifications Initiative 4B, Risk-Managed Technical Specifications (RMTS) Guidelines, October 2012 (ADAMS Package Accession No. | |||
ML122860402). | |||
* Regulatory Guide 1.174, Revision 3, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis, January 2018 (ADAMS Accession No. | |||
ML17317A256). | |||
2 2}} | 2 2}} | ||
Revision as of 23:32, 19 October 2019
| ML19064B075 | |
| Person / Time | |
|---|---|
| Issue date: | 01/30/2019 |
| From: | Jonathan Evans, Hartle B NRC/NRR/DRA |
| To: | |
| References | |
| Download: ML19064B075 (22) | |
Text
Risk-Informed Technical Specification Initiative 4b: Risk-Informed Completion Times Brandon Hartle, Reliability and Risk Analyst Jonathan Evans, Reliability and Risk Analyst PRA Licensing Branch A, Division of Risk Assessment, NRR NEI Lessons-Learned Workshop, January 30 - 31, 2019
Executive Summary
- TSTF-505 Rev. 1 suspended November 2016
- Revision resolves issues, except Loss of Function Conditions
Initiative 4b Overview
- Risk-Informed process to extend TS CTs based on plant configuration
- Risk evaluation using current configuration to calculate a specific CT called Risk-informed Completion Time (RICT)
- Frontstop = existing TS CT
- Backstop = 30 day maximum
- Applies to planned and emergent conditions 3
Initiative 4b Overview
- NEI 06-09 Rev. 0
- Introduced term PRA Functional as an alternative to Operable and allowed a RICT for all PRA Functional configurations
- This replaces design basis analysis requirements with PRA success criteria in the TSs
- Restricted definition of PRA Functional as capable of meeting design basis analysis requirements or appropriate disposition or programmatic restriction will be provided
- A RICT can only apply to (restorative) TS Required Actions that are not Mode changes or unit shutdown 4
Attributes of a RICT Program
- Integrates Plant Risk
- Manage multiple SSC outages
- Manage broader scope of SSCs (TS and non-TS)
- Flexible Configuration Management
- Decisions include real-time risk insights
- Focus on repair, not necessarily shutdown
- Emergent problems
- Ongoing/continuous risk awareness 5
Description of TSTF-505 Rev. 1
- Defined Conditions, Required Actions, and CTs within scope
- Added a new program in TS Chapter 5, "Administrative Controls," entitled the "Risk-Informed Completion Time Program."
- Provided additional clarity for RICT entry using PRA Functional to extend CT for loss of function (LOF) mode change conditions (e.g., 3.0.3 conditions) 6
Early Challenges for TSTF-505 Rev. 1
- Vogtle pilot 4b review on-going in 2016
- 5 other TSTF-505 reviews submitted before pilot completed
- Implementation of the TSTF in these LARs would have resulted in indeterminate and potentially substantive reduction in safety margin 7
Issues With TSTF-505 Rev. 1
- Included PRA Functional to extend CT for configurations with loss of capability to achieve design basis success criteria
- Added new TS 3.0.3 Conditions and Required Actions to replace default TS 3.0.3 entry and included PRA Functional to extend CTs in the new TS
- Included (in model TSTF-505 SE) justification for adequate defense-in-depth and safety margin which relied on assuming NRCs restricted definition of PRA Functional, without additional disposition or programmatic restrictions for TS 3.0.3 and mode change CTs 8
TSTF-505 Rev. 1 Suspension
- NRC staff suspended approval of TSTF -505, Rev.1, explaining concerns identified during review of plant-specific LARs:
- Definition of PRA Functional
- SE on NEI 06-09 limited use of PRA Functionality by requiring remaining performance capability to meet design basis analysis requirements (e.g., maintain functional capability to perform at level of one operation train)
- TS Conditions Involving Mode Changes or Unit Shutdowns
- SE on NEI 06-09 a RICT can only apply to (restorative) TS Required Actions that are not Mode changes or unit shutdown 9
TSTF-505 Rev. 1 Condition B does not meet design basis analysis requirements, therefore, would not meet intent of SE for NEI 06-09 1
0
TSTF-505 Rev. 2 1
1
TSTF-505 Rev. 2 Changes
- Removed Loss of Function Conditions
- Staff concerned with maintaining adequate defense in depth and safety margins
- The conditions in Table 1 require additional justification that those are not Loss of Function
- Newly Developed PRA Method Administrative Control Constraint
- Conditions not modeled in the PRA are in scope
- Can be plant specific, PRA model dependent
- Table 1 in Model application requires additional justification 1
2
TSTF-505 Rev. 2 Changes
- Common Cause Failures (CCF)
- Included in the TS Admin Section to address emergent failures
- CCF PRA Modeling to be handled on a plant specific basis
- All hazards require technically adequate dispositions
- External hazards need to be systematically considered
- Addressing only the impact on baseline risk is insufficient
- Impact on configuration specific change in risk should be addressed 1
3
Initiative 4b Loss of Function Considerations
- 4b allows the use of PRA Functional and calculation of RICT when all trains are Inoperable
- But available equipment can provide design basis success parameters upon demand OR
- Define and justify adequate defense in depth and safety margins when available equipment can only provide PRA success parameters
- Change in Backstop for CT upon Inoperability of all trains from 30 days to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
- Consistent with approved and used TSTF-426 which allows a maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> when all trains are Inoperable 1
4
Initiative 4b Loss of Function Considerations
- Using design basis success criteria for PRA Functional for loss of all trains alleviates need for justifying PRA success criteria, i.e.,
- Use only SSCs relied on in the original TS specified safety function
- Ensure design basis success criteria for parameters are met for all design basis initiators
- May deviate by requesting TS changes for Inoperability of all trains using PRA Functional with supporting information
- This review may be complex and resource intensive
- Suggest only using on a limited basis 1
5
TSTF-505 and 4b LAR Content 4b, Risk-Informed Completion Times
- More flexibility for technical 50.69 SSC Categorization licensee robustness, and plant representation 5b, Risk-Informed
- More complex staff Surveillance Frequencies review Risk-Informed Inservice Inspection 1
6
- Scope, level of detail, and technical adequacy of PRA are to be commensurate with application
- Requires confidence in plant specific PRA models
- Up-to-date full-scope PRA peer reviews
- Supporting Requirements assessed to Capability Category II for all PRA hazards
- Facts and Observations (F&Os) resolved or dispositioned prior to LAR submittal
- Deviations from NRC accepted guidance and pilot applications add to review time and resources 1 7
4b Application Review Best Practices
- Pre-submittal meetings
- Familiarizes staff with licensees strategy and goals
- Allows for clarifications to reduce acceptance review pitfalls
- Reviewing recent submittals
- Helps licensee anticipate and address common RAIs
- Minimizes deviations from acceptable approaches/templates
- F&O Closure Observations
- Audits
- Assists with NRC review of complex 4b applications
- Clarifies information in the LAR to reduce RAIs 1
8
Conclusions
- Revision resolves issues, except for loss of function conditions
- 3 Initiative 4b LARS in house; 3 SEs issued
- 3 LARs in house for TSTF-505 Rev. 2
- Complex reviews that rely on the technical adequacy of the PRA
- High quality submittals needed to support efficient review by the NRC
- Progress/Path forward
- With issuance of the SE for TSTF-505 Rev. 2, we expect a large number of submittals in 2019
- Reviewing previous submittals and using best practices will facilitate efficient NRC review 1
9
List of Acronyms
- CC - Capability Category
- CCF - Common Cause Failure
- CDF - Core Damage Frequency
- CT - Completion Time
- F&O - Facts and Observations
- LAR - License Amendment Request
- NRC - Nuclear Regulatory Commission
- RAI - Request for Additional Information
- RICT - Risk Informed Completion Time
- SE - Safety Evaluation
- SR - Supporting Requirement
- SSC - Systems, Structures, and Components
- TS - Technical Specification
References
- TSTF-505, Revision 1, Provide Risk-Informed Extended Completion Times
- RITSTF Initiative 4b, June 14, 2011, and Model Application dated January 31, 2012 (ADAMS Accession No. ML120330410).
- Draft Revised Model Safety Evaluation of TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b, May 1, 2018 (ADAMS Accession No. ML17290A005).
- Letter from Timothy J. McGinty, U.S. Nuclear Regulatory Commission, to Technical Specifications Task Force, Issues With Technical Specifications Task Force Traveler TSTF-505, Revision 1, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4B, dated November 15, 2016 (ADAMS Accession No. ML16281A021).
- Final Safety Evaluation For Nuclear Energy Institute (NEI) Topical Report (TR) NEI 06 09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines, May 17, 2007 (ADAMS Accession No. ML071200238). 2 1
References
- Topical Report NEI 06-09, Revision 0-A, Risk-Informed Technical Specifications Initiative 4B, Risk-Managed Technical Specifications (RMTS) Guidelines, October 2012 (ADAMS Package Accession No.
- Regulatory Guide 1.174, Revision 3, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis, January 2018 (ADAMS Accession No.
2 2