TSG-DORL-2021-01, NRR Temporary Staff Guidance - Risk-Informed Process for Evaluations: Difference between revisions

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#REDIRECT [[TSG-DORL-2021-01, Temporary Staff Guidance TSG-DORL-2021-01, Revision 1, Risk-Informed Process for Evaluations]]
| number = ML20261H473
| issue date = 01/05/2021
| title = NRR Temporary Staff Guidance - Risk-Informed Process for Evaluations
| author name = Erlanger C
| author affiliation = NRC/NRR/DORL
| addressee name =
| addressee affiliation =
| docket =
| license number =
| contact person = Klett, A.
| case reference number = EPID L-2019-LRO-0074, TSG-DORL-2021-01
| package number = ML20261H475
| document type = NRR Office Instruction
| page count = 18
| project = EPID:L-2019-LRO-0074
| stage = Other
}}
 
=Text=
{{#Wiki_filter:U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation NRR Temporary Staff Guidance Temporary Staff Guidance No.:  TSG-DORL-2021-01 Temporary Staff Guidance
 
==Title:==
RISK-INFORMED PROCESS FOR EVALUATIONS Effective Date:                January 5, 2021 Approved By:                    Craig G. Erlanger Date Approved:                  December 2, 2020 Primary
 
==Contact:==
T. Reed                A. Zoulis 301-415-1462            301-415-1209 Timothy.Reed@nrc.gov    Antonios.Zoulis@nrc.gov Responsible Organization:      NRR/DORL ADAMS Accession No.:            ML20261H473 Page 1 of 18
 
ML20261H473 ADAMS Accession No. ML20261H473                              *by e-mail OFFICE    NRR/DORL/LPLX/PM*        NRR/DORL/LPLX/LA*        NRR/DORL/LPLX/BC*
NAME      TReed                    PBlechman                JDixon-Herrity DATE      9/17/2020                10/1/2020                10/20/2020 OFFICE    OGC-NLO*                  NRR/DORL/D*
NAME      JGillespie/JScro          CErlanger DATE      12/2/2020                12/2/2020 Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests
: 1. OBJECTIVE This temporary staff guidance document provides the Office of Nuclear Reactor Regulation (NRR) staff the framework for streamlined processing of license amendments requests (LARs) and exemptions from U.S. Nuclear Regulatory Commission (NRC) requirements that are submitted under the Risk-Informed Process for Evaluations (RIPE). Use of this guidance is limited to issues for which the safety impact associated with an issue addressed by an exemption request or a LAR can be modeled using probabilistic risk assessment (PRA). These issues could be identified through inspections, corrective actions, or other licensee or regulatory processes.
NRRs Division of Risk Assessment (DRA) is the lead technical division required to provide an evaluation input for a RIPE submittal. The NRCs review is streamlined in that RIPE is based on the application of pre-existing risk-informed criteria that allow for review and disposition of the submittal with minimal resources.
This temporary staff guidance provides the NRR staff with expectations and flexibilities that replace or supplement the routine exemption and LAR review processes described in NRR Office Instructions LIC-103, Exemptions from NRC Regulations (Section 3 of this TSG), and LIC-101, License Amendment Review Procedures (Section 4 of this TSG) for requests that meet the RIPE requirements.
: 2. BACKGROUND RIPE is available to licensees with approved and implemented amendments for Title 10 of the Code of Federal Regulations (10 CFR) Section 50.69, Risk-informed categorization and treatment of structures, systems and components for nuclear power plants, Integrated Decision-Making Panel (IDP) and Technical Specifications Task Force (TSTF) Traveler 505, Provide Risk Informed Extended Completion Times -
RITSTF [Risk-Informed TSTF] Initiative 4b.1 Licensees that have implemented an NRC-approved amendment to adopt 10 CFR 50.69 and TSTF-505 can leverage these initiatives to perform safety impact characterizations using RIPE and request licensing actions with the expectation that the NRC will use a streamlined review process if the issue is characterized as having a minimal safety impact. In addition, the NRC may also utilize RIPE streamlined review for submittals by licensees that have applied a TSTF-505 approved amendment and a RIPE IDP, as documented in Nuclear Energy Institute (NEI) guidance, NEI Guidelines for the Implementation of the Risk-Informed Process for Evaluations Integrated Decision-Making Panel (ADAMS Accession No. ML20245E147).
1 NRC has approved some licensee programs for Risk-informed Completion Times consistent with NEI 06-09 Risk-Informed Technical Specifications Initiative 4B, Risk-Managed Technical Specifications (RMTS) Guidelines, which also can be used in lieu of TSTF-505 for RIPE. Any references in this TSG to TSTF-505 also include NEI 06-09.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests For RIPE, all the following must apply in order to characterize an issue as having a minimal safety impact:
* The issue contributes less than 1 x 10-7/year to core damage frequency (CDF).
* The issue contributes less than 1 x 10-8/year to large early release frequency (LERF).
* The issue has no safety impact or minimal safety impact in accordance with Guidelines for Characterizing the Safety Impact of Issues.
* Cumulative risk is assessed based on plant-specific CDF and LERF. Cumulative risk is acceptable for the purposes of this guidance if baseline risk remains less than 1 x 10-4/year for CDF and less than 1 x 10-5/year for LERF once the impact of the proposed change is incorporated into baseline risk If the safety impact cannot be characterized as minimal, then the submittal does not qualify for the NRC streamlined RIPE review. The NRC, however, may still review the LAR or exemption request through its normal process (i.e., not using the streamlined RIPE review).
Examples of issues for which this process may be used include, but are not limited to, the following:
* Actions needed to address inspection findings.
* Resolution of issues identified through other regulatory or licensee processes.
* Responses to orders requiring changes or modifications to the plant.
* Generic issues requiring changes or modifications to the plant.
RIPE may not be used for the following:
* Any immediate actions necessary for continued safe operation (e.g., to restore compliance with a technical specification (TS) or remove a threat to personnel safety).
* Any immediate repairs necessary for continued power production (e.g., replacing a damaged main transformer).
* Any issues for which the safety impact cannot be directly assessed using PRA (e.g.,
fuel changes, changes to emergency planning programs, or changes to security).
* Changes to the TSs.
: 3. EXEMPTIONS: LIC-103 REVISION 2 BASIC REQUIREMENTS, REPLACEMENTS, OR SUPPLEMENTS 3.1. Work Planning (Supplement to LIC-103, Revision 2, Basic Requirement 4.1, Exemption Processing)
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests When a Division of Operating Reactor Licensing (DORL) project manager (PM) receives the RIPE exemption request from a licensee, the PM will initiate a new project in the reactor program system (RPS). The PM should title the project as
[Plant Name] - [RIPE] Part XX Exemption.
A RIPE submittal is limited to issues for which the safety impact associated with an issue addressed by an exemption request can be modeled directly or with surrogates using PRA. The licensees streamlined exemption technical justification is a risk-related justification that leverages previous NRC evaluations and approvals regarding the plants adoption of 10 CFR 50.69 IDP, or equivalent, and TSTF-505 license amendments. Therefore, one of DRAs PRA branches will be assigned to review a RIPE exemption request and will be the lead branch providing an evaluation input. The DORL PM should also assign other technical and environmental branches depending on the subject matter of the request, but those branches will be assigned initially as concurrence only.
An environmental review by NRCs Environmental Center of Expertise (EnvCOE) may also be required if the action is not categorically excluded under 10 CFR 51.22(c).
See Tables 3.1 and 3.2 in Section 3.2 for the creation of the schedule milestones.
3.2. Acceptance Review (Supplement to LIC-103, Revision 2, Section 4.2, Review Request for Completeness and Acceptability)
An acceptance review in accordance with LIC-109, Acceptance Review Procedures, will be followed for RIPE exemption requests, with the additions and exceptions noted below.
The PM, DRA reviewer, EnvCOE reviewer (if required), and the engineering technical reviewer(s) determine during the acceptance review that the submittal meets all the following criteria for receiving a streamlined review under RIPE:
The application clearly meets a categorical exclusion under 10 CFR 51.22(c).
The non-DRA branches do not have any requests for additional information, do not need to provide any written evaluation input, and will serve only a minimal consultation role in the review.
The criteria discussed in Section 2 of this TSG and in the paragraph below are met for processing the application under RIPE.
In addition to the completeness and acceptability items listed in LIC-103, Revision 2, Section 4.2, an exemption is eligible for a streamlined review if the following elements are included:
The issue that qualifies the exemption request for the RIPE streamlined process is well defined.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests The RIPE submittal confirms that the plant has implemented an NRC approved TSTF-505 risk-informed technical specification amendment and has completed all associated license conditions.
The RIPE submittal confirms that the plant has implemented an NRC approved amendment to adopt the 10 CFR 50.69 IDP, or equivalent, and has completed all associated license conditions.
The RIPE submittal includes the results of the IDPs review of the issue addressed in the submittal.
The RIPE submittal states that the issue has no or minimal safety impact, meaning the following are addressed in the request:
o The issue contributes less than 1 x 10-7/year to CDF, o The issue contributes less than 1 x 10-8/year to LERF, o The issue has no or minimal safety impact in accordance with Guidelines for Characterizing the Safety Impact of Issues, and o Cumulative risk, on a plant-specific basis, is assessed to be less than 1 x 10-4/year for CDF and less than 1 x 10-5/year for LERF once the impact of the proposed change is incorporated into baseline risk.
As described in Section 2.0 of this TSG, RIPE may not be used to support immediate actions or repairs. Verbal exemption approvals will not be completed using RIPE.
If the PM and the DRA, environmental, and engineering reviewers determine during the acceptance review that the exemption request does not contain the information necessary to qualify as a RIPE submittal (with branch chief approval), that more information through a supplement is required, or that the application is non-acceptable, then the acceptance review results will either be non-acceptable or non-acceptable with an opportunity to supplement, and the LIC-109 process will be followed. If the licensee responds with a supplement that is acceptable for review but still does not qualify for a streamlined review under RIPE, then the PM will notify the licensee that the request will continue to be processed under a normal NRC review schedule, and the PM in consultation with LPMB (if required) will revise the Enterprise Project Identifier (EPID) title by removing [RIPE] from it.
The acceptance review for a RIPE submittal will follow the tasks and streamlined milestone schedule below, assuming the submittal meets the criteria for a streamlined review and is acceptable for review:
Table 3.1, Acceptance Review Milestones for a RIPE Exemption ACCEPTANCE REVIEW MILESTONES                              SCHEDULE 1    PM creates project in the NRR workload                    T* = 0 management tool 2    PM reviews submittal for information sufficiency          < T = 14 days (2 weeks)
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests 3    Technical staff provide results of technical                    < T = 14 days sufficiency review to PM                                        (2 weeks) 4    PM notifies licensee or applicant (e.g., via call, e-            < T = 21 days mail or letter) that the submittal meets the criteria for        (3 weeks) a streamlined review and is acceptable for review 5    PM records the date of acceptance review                        < T = 21 days notification in the NRR workload management tool                (3 weeks)
* T = Time from date when RIPE exemption request is declared an Official Agency Record in ADAMS (in calendar days and weeks).
If the submittal was not acceptable for review or had to be supplemented, then the milestone schedules per LIC-109 would be followed. The predetermined content and structure of a RIPE exemption request that has been determined to contain the RIPE-related items described above will be planned with a streamlined schedule as shown in Table 3.2 (in calendar days and weeks),
assuming the application is acceptable for review.
The work schedule described in Table 3.2 allows for an approximate 90-day review of RIPE exemption requests. This schedule does not accommodate the issuance and licensee response to requests for additional information (RAIs);
however, this schedule may be able to accommodate the request for confirmation of information (RCI) process for certain issues. The streamlined RIPE review is predicated on the issue being justified as having minimal or no safety impact with the RIPE limitations and review elements clearly and completely addressed in the submittal. Should the engineering or environmental reviewers conclude that an RAI is still required, the submittal cannot be dispositioned under the RIPE streamlined review, and the normal work schedule milestones will apply. The PM in consultation with LPMB (if required) will notify the licensee if this occurs and develop new work schedule milestones.
Table 3.2, Project Milestones for a RIPE Exemption TECHNICAL REVIEW AND PROCESSING                                SCHEDULE*
MILESTONES 1    DRA exemption review input provided to PM                      < T = 49 days (7 weeks) 2    EnvCOE provide environmental review to PM (if                  < T = 49 days required)                                                      (7 weeks) 3    PM provides exemption package to OGC                          < T = 63 days (9 weeks) 4    OGC provides NLO to PM                                        < T = 77 days (11 weeks) 5    NRC completes its review of exemption (DORL                    < T = 91 days Division Director (or delegate) to sign)                      (13 weeks)
              *continued from the schedule in Table 3.1, assuming the submittal was acceptable for review.
3.3. Technical Review (Supplement to LIC-103, Revision 2, Basic Requirement 4.5, Technical Review of the Proposed Exemption) 3.3.1. Implementation of Amendments to Adopt 10 CFR 50.69 IDP or Equivalent and TSTF-505 Page 7 of 18
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests RIPE can only be used by and for licensees that have implemented NRC-approved amendments for risk-informed initiatives 10 CFR 50.69 IDP (or equivalent) and TSTF-505. RIPE builds on the licensees expanded use of PRA models for making day-to-day decisions and benefit from the use of IDPs that were constituted as part of implementation of 10 CFR 50.69 and other initiatives. Licensees need to have implemented the IDP process and completed any license conditions associated with implementation of 10 CFR 50.69 and TSTF-505 for the staff to use the streamlined review process, but the licensee does not need to have characterized any structures, systems, or components in accordance with 10 CFR 50.69. In addition, licensees that choose to apply a RIPE IDP, as documented in the NEI guidance, can also leverage the streamlined process.
The DRA technical reviewer will confirm that the IDP evaluation results, including a summary of the basis for each decision, is documented in the exemption request. In particular, the reviewer should confirm that the licensee dispositioned any considerations identified by an industry or NRC generic assessment expert team (GAET) and how they apply to the plant, and a basis for any plant-specific departures from the GAET assessment. The level of documentation should be such that the licensee provides a sufficient basis for a knowledgeable individual to independently review the information and reach the same conclusion.
The basis for any engineering judgment and the logic used in the assessment should be documented to the extent practicable and to a degree commensurate with the safety impact and complexity of the issue. The items considered by the GAET, IDP and the licensees subject matter expert should be clearly stated.
3.3.2. Use of Acceptable/Approved PRA Model In order to expedite the review, the DRA technical reviewer must confirm that the licensee has implemented an acceptable TSTF-505 model in order to leverage their PRA models to perform quantitative risk assessments to support using this process. To do so, each of the following conditions apply:
The issue is completely within the scope of the licensees PRA model or can be bounded using surrogates.
The licensee has implemented an IDP consistent with risk-informed initiative 10 CFR 50.69 or equivalent.
The licensee has implemented risk-informed initiative TSTF-505 and has completed all associated license conditions.
The licensees PRA model was found acceptable to support a TSTF-505 applications by the NRC.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests The issue is within the scope of the portion(s) of the PRA model that was found acceptable by the NRC.
The plant-specific PRA must include the capability to assess CDF and LERF, and the risk evaluation must include a quantified assessment of all significant sources of risk (i.e., external events, internal flooding, and fires) that can be impacted by the issue being assessed. Where PRA models are not available, the licensee may perform conservative or bounding analyses to quantify the risk impact (e.g., external events, low power and shutdown).
3.3.3. Evaluation of PRA Results The DRA technical reviewer will confirm that the licensee calculated the changes in CDF and LERF as the difference in the risk with the proposed change and to the plant without the proposed change. The risk analysis may not include any credit for proposed risk management actions (RMAs) or other activities implemented to reduce the risk impact associated with the issue. The risk analysis must document any assumptions made when performing the risk evaluation, whether any parts of the issue were outside the scope of the licensees PRA, and whether any surrogates were used to account for the impact of the issue. The final quantitative risk analysis must include an evaluation of the impact on internal events risk, as well as the impact on any relevant external events.
The PRA results will be compared to the relative change in risk of the licensees overall CDF and LERF. An issue is not risk-significant (i.e.,
minimal or less than minimal) if all of the following apply:
* the issue contributes less than 1 x 10-7/year to CDF, and
* the issue contributes less than 1 x 10-8/year to LERF.
If the risk results are less than the criteria above, the issue is considered to have a minimal impact on safety.
3.3.4. Assessment of the Need for Risk Management Actions If the issue assessed in the RIPE exemption request was determined to have no safety impact, then (RMAs) are not required. However, if the issue was determined to have a minimal impact on safety, then RMAs should be considered to offset the risk increase due to the issue.
RMAs are typically associated with managing configuration risk when equipment is out of service or for temporary changes. However, in the case of a RIPE application, the proposed change will become the permanent plant configuration if the exemption request is approved.
Therefore, only long-term actions to reduce risk associated with the new configuration should be considered, such as permanent procedure changes or simple plant modifications. For example, if an automatic Page 9 of 18
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests interlock is defeated permanently, procedure changes to verify proper manual operation of the equipment may be appropriate to reduce the risk associated with removal of the automatic interlock.
3.3.5. Additional Considerations Ensure the issue is well-defined: Confirm that the specific issue is appropriately defined and articulated in order to illustrate the safety impact due to the issue.
Realism so as to not bias the assessment: The level of realism and analyses will vary depending on the issue, but in order to avoid bias, realistic analysis is the objective. The licenses assessment should include sensitivity analyses to address the key assumptions and sources of uncertainty that are driving the results. If the risk impact is exceedingly small, or clearly large, then a bounding evaluation may suffice.
Uncertainty considerations: Sensitivity analysis should be performed, commensurate with the impact of the issue, to address any key assumptions and sources of uncertainty that may influence the results.
Evaluation of the overall nature of the risk impact of a potential action:
Both beneficial and adverse effects should be considered (e.g.,
replacing a small pump with a large pump could reduce the available margin of an emergency diesel generator, or closing and depowering pressurizer power operated relief valve block valves to prevent spurious operation could reduce effectiveness of feed and bleed operations).
Identifying the extent of the impact: The specific intended impact of the issue, as well as other related or indirect effects, should be addressed (e.g., FLEX provides mitigation for more than external hazards even though that is its fundamental intended purpose). In other words, one specific issue could impact the specific function under consideration as well as multiple other separate plant functions. This could include both positive and negative impacts that may not be immediately evident if the impacts of the issue are considered independently.
3.4. Emergency Plans (Replacement for LIC-103, Revision 2, Basic Requirement 4.7, Exemptions that Result in a Decrease in Effectiveness of the Emergency Plan)
RIPE is not applicable to any issues for which the safety impact cannot be directly assessed using PRA. Therefore, exemption requests related to the emergency plans will not be considered under the RIPE streamlined review process.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests 3.5. Design Certification Rule (Replacement for LIC-103, Revision 2, Basic Requirement 4.8, Exemptions Referencing a Design Certification Rule)
Section 52.63(b)(1) of 10 CFR allows a licensee who references a design certification rule to request an exemption from elements of the certification information. However, RIPE is only applicable to operating plants and will not be considered for review of exemptions for elements of design certification information.
3.6    Preparation of Exemption (Supplement to LIC-103, Revision 2, Basic Requirement 4.10, Preparation of Work Products, Exemption Document)
In addition to verifying that special circumstances exist, Section III.A of the exemption will include defense-in-depth and safety margin conclusions assessed by the IDP as documented in the RIPE exemption request.
Section III.B of the exemption will include the RIPE safety evaluation input, including verification that TSTF 505 and 10 CFR 50.69 amendments have been approved and implemented at the plant and that all associated license conditions have been completed. In addition, if an alternate IDP is used, the SE will verify the IDP is equivalent to the 50.69 IDP and can be used to support the NRCs safety conclusion. Section III.B will also reflect that the issue described in the exemption request is within the scope of the licensees PRA and that the risk impact was modeled using the TSTF-505 technically acceptable model.
: 4. LICENSE AMENDMENT REQUESTS: LIC-101, REVISION 6, APPENDIX B REPLACEMENTS OR SUPPLEMENTS 4.1. Work Planning and Acceptance Review (Supplement to LIC-101, Revision 6 Appendix B, Section 2.0) 4.1.1. Opening a Project in RPS When a PM receives the RIPE LAR from a licensee, the PM will initiate a new project in RPS. The PM should title the project as [Plant Name] -
[RIPE] LAR to [subject of LAR].
A RIPE submittal is limited to issues for which the safety impact associated with an issue addressed by a LAR can be modeled directly or with surrogates using PRA. The licensees LAR technical justification is a risk-related justification that leverages previous NRC evaluations and approvals regarding the plants adoption of 10 CFR 50.69 IDP, or equivalent, and TSTF-505 license amendments. Therefore, one of DRAs PRA branches will be assigned to review a RIPE LAR and will be the lead branch providing a safety evaluation input. The PM should also assign other technical and environmental branches depending on the subject matter of the request, but those branches will be assigned initially as concurrence only.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests An environmental review by the EnvCOE may also be required if the action is not categorically excluded under 10 CFR 51.22(c). See Tables 4.1 and 4.2 in Section 4.1.2 for the creation of the schedule milestones.
4.1.2  Acceptance Review An acceptance review in accordance with LIC-109, Acceptance Review Procedures, will be followed for RIPE LARs, with the following additions and exceptions.
The PM, DRA reviewer, EnvCOE reviewer (if required), and the engineering technical reviewer(s) determine during the acceptance review that the submittal meets all the following criteria for receiving a streamlined review under RIPE:
The application clearly meets a categorical exclusion under Title 10 of the Code of Federal Regulations (10 CFR), Part 51, Section 51.22(c).
The non-DRA branches do not have any requests for additional information, do not need to provide any written evaluation input, and will serve only a minimal consultation role in the review.
The criteria discussed in Section 2 of this TSG and in the paragraph below are met for processing the application under RIPE.
In addition to the acceptance review elements described in LIC-101, Revision 6, Appendix B, Section 2.3, a LAR is eligible for a streamlined review if the following elements are included:
The issue that qualifies the LAR for the RIPE is well defined.
The RIPE submittal confirms that the plant has implemented an NRC approved TSTF-505 risk-informed technical specification amendment and has completed all associated license conditions.
The RIPE submittal confirms that the plant has implemented an NRC approved amendment to adopt the 10 CFR 50.69 IDP, or equivalent, and has completed all associated license conditions.
The RIPE submittal includes the results of the IDPs review of the issue addressed in the submittal.
The RIPE submittal states that the issue has no or minimal safety impact, meaning the following are addressed in the request:
o The issue contributes less than 1 x 10-7/year to CDF; o The issue contributes less than 1 x 10-8/year to LERF; o The issue has no or minimal safety impact in accordance with Guidelines for Characterizing the Safety Impact of Issues.; and o Cumulative risk, on a plant-specific basis, is assessed to be less than 1 x 10-4/year for CDF and less than 1 x 10-5/year for LERF once the impact of the proposed change is incorporated into baseline risk.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests If the PM and DRA, environmental, and engineering reviewers determine during the acceptance review that the LAR does not contain the information necessary to qualify as a RIPE submittal (with branch chief approval), that more information through a supplement is required, or that the application is non-acceptable, then the acceptance review results will either be non-acceptable or non-acceptable with an opportunity to supplement, and the LIC-109 process will be followed. If the licensee responds with a supplement that is acceptable for review but still does not qualify for a streamlined review under RIPE, then the PM will notify the licensee that the request will continue to be processed under a normal NRC review schedule, and the PM in consultation with LPMB (if required) will revise the Enterprise Project Identifier (EPID) title by removing [RIPE] from it.
The acceptance review for a RIPE submittal will follow the tasks and streamlined milestone schedule below, assuming the submittal meets the criteria in the previous paragraph and is acceptable for review:
Table 4.1, Acceptance Review Milestones for a RIPE LAR ACCEPTANCE REVIEW MILESTONES                                SCHEDULE 1  PM creates project in the NRR workload                      T* = 0 management tool 2  PM reviews submittal for information sufficiency            < T = 14 days (2 weeks) 3  Technical staff provide results of technical                < T = 14 days sufficiency review to PM                                    (2 weeks) 4  PM notifies licensee or applicant (e.g., via call, e-      < T = 21 days mail or letter) that LAR meets the criteria for a          (3 weeks) streamlined review and is acceptable for review 5  PM records the date of acceptance review                    < T = 21 days notification in the NRR workload management                (3 weeks) tool
                  *T = Time from date when RIPE LAR is declared an Official Agency Record in ADAMS (in calendar days and weeks)
If the submittal was not acceptable for review or had to be supplemented, then the milestone schedules per LIC-109 would be followed. The predetermined content and structure of a RIPE LAR that has been determined to contain the RIPE-related items described above will be planned with a streamlined schedule as shown in Table 4.2 (in calendar days and weeks), assuming the application is acceptable for review.
The work schedule described in Table 4.2 allows for an approximate 140-day streamlined review of RIPE LARs. This schedule does not accommodate the issuance and licensee response to RAIs; however, the staff may be able to accommodate sufficient time for the RCI process for specific issues. The streamlined RIPE review is predicated on the issue being justified as having minimal or no safety impact with Page 13 of 18
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests the RIPE limitations and review elements clearly and completely addressed in the submittal. Should the technical or environmental review process determine that an RAI is required, the submittal cannot be dispositioned under the RIPE streamlined process, and the NRCs normal work schedule milestones will be applied. The PM in consultation with LPMB (if required) will notify the licensee if this occurs and develop new work schedule milestones.
Table 4.2, Project Milestones for RIPE LAR TECHNICAL REVIEW AND PROCESSING                          SCHEDULE*
MILESTONES 1    PM issues the notice of application in Federal < 42 days Register                                                  (6 weeks) 2    DRA SE input provided to PM                              < 70 days (10 weeks) 3    EnvCOE provide environmental review to PM < 70 days (if required)                                            (10 weeks) 4    PM provides amendment package to OGC                      < 105 days (15 weeks) 5    OGC provides NLO to PM                                    < 119 days (17 weeks) 6    NRC completes its review of the LAR                      < 140 days (20 weeks)
* Continued from the schedule in Table 4.1, assuming the submittal was acceptable for review 4.2. Public Noticing (Replacement for LIC-101, Revision 6 Appendix B, Section 3.0, Public Notification)
The PM ensures that a 28-day notice is published in the Federal Register.
However, the notice cannot be published before the acceptance review is complete. The notice may be published within 42 days (6 weeks) of the declaration of the LAR submittal as an official agency record in ADAMS to provide for the 30-day public comment period and 60-day period to request a hearing to facilitate a streamlined (i.e., approximately 140-days) RIPE review schedule for the LAR.
4.3. Safety Evaluation (Supplement to LIC-101, Revision 6 Appendix B, Section 4.0, Safety Evaluation)
The RIPE SE input will document NRCs evaluation of defense-in-depth and safety margin conclusions assessed by the IDP, as documented in the RIPE LAR. The RIPE SE input will also include verification that TSTF-505 and 10 CFR 50.69 amendments have been approved and implemented at the plant and that all associated license conditions have been completed. In addition, if an alternate IDP is used, the SE will verify the IDP is equivalent to the 10 CFR 50.69 IDP and can be used to support the NRCs safety conclusion.
Finally, the SE input will reflect that the issue described in the LAR is within the scope of the licensees PRA and that the risk impact was modeled using the TSTF-505 technically acceptable model.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests 4.3.1. Implementation of amendments to adopt 10 CFR 50.69 IDP, or equivalent, and TSTF-505 The RIPE streamlined process can only be used by and for licensees that have implemented NRC-approved amendments for 10 CFR 50.69 IDP, or equivalent, and TSTF-505. RIPE builds on the licensees expanded use of PRA models for making day-to-day decisions and benefit from the use of IDPs that were constituted as part of implementation of 10 CFR 50.69 and other initiatives. Licensees need to have implemented the IDP process and completed any license conditions associated with implementation of 10 CFR 50.69 and TSTF-505 for the staff to use the streamlined review process, but the licensee does not need to have characterized any systems, structures, or components in accordance with 10 CFR 50.69. In addition, licensees that choose to apply a RIPE IDP, as documented in NEI guidance (ADAMS Accession No. ML20245E147), can also leverage the streamlined process.
The DRA technical reviewer will confirm that the IDP evaluation results, including a summary of the basis for each decision, is documented in the LAR. In particular, the reviewer should confirm that the licensee dispositioned any considerations identified by an industry or NRC generic assessment expert team (GAET) and how they apply to the plant, and a basis for any plant-specific departures from the GAET assessment. The level of documentation should be such that a sufficient basis is provided for a knowledgeable individual to independently review the information and reach the same conclusion.
The basis for any engineering judgment and the logic used in the assessment should be documented to the extent practicable and to a degree commensurate with the safety impact and complexity of the issue. The items considered by the GAET, IDP, and the licensees subject matter expert should be clearly stated.
4.3.2. Use of acceptable/approved PRA model In order to expedite the review, the DRA technical reviewer must confirm that the licensee has implemented an acceptable TSTF-505 technically acceptable model in order to leverage their PRA models to perform quantitative risk assessments to support using this process. To do so, each of the following conditions apply:
The issue is completely within the scope of the licensees PRA model or can be bounded using surrogates.
The licensee has implemented and IDP consistent with 10 CFR 50.69 or equivalent.
The licensee has implemented risk-informed initiative TSTF-505 and has completed all associated license conditions.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests The licensees PRA model was found acceptable to support a TSTF-505 application by the NRC.
The issue is within the scope of the portion(s) of the PRA model that was found acceptable by the NRC.
The plant-specific PRA must include the capability to assess CDF and LERF, and the risk evaluation must include a quantified assessment of all significant sources of risk (i.e., external events, internal flooding, and fires) that can be impacted by the issue being assessed. Where PRA models are not available, conservative or bounding analyses may be performed to quantify the risk impact (e.g., low power and shutdown).
4.3.3. Evaluation of PRA Results The DRA technical reviewer will confirm that the licensee calculated the changes in CDF and LERF as the difference in the risk with the proposed change and to the plant without the proposed change. The risk analysis may not include any credit for proposed RMAs or other activities implemented to reduce the risk impact associated with the issue. The risk analysis must document any assumptions made when performing the risk evaluation, whether any parts of the issue were outside the scope of the licensees PRA, and whether any surrogates were used to account for the impact of the issue. The final quantitative risk analysis must include an evaluation of the impact on internal events risk, as well as the impact on any relevant external events.
The PRA results will be compared to the relative change in risk of the licensees overall CDF and LERF. An issue is not risk-significant (i.e.,
minimal or less than minimal) if all of the following apply:
* the issue contributes less than 1 x 10-7/year to CDF, and
* the issue contributes less than 1 x 10-8/year to LERF.
If the risk results are less than the criteria above, the issue is considered to have a minimal impact on safety.
4.3.4. Assessment of the Need for Risk Management Actions If the issue assessed in the LAR was determined to have no safety impact, then RMAs are not required. However, if the issue was determined to have a minimal impact on safety, then RMAs should be considered to offset the risk increase due to the issue.
RMAs are typically associated with managing configuration risk when equipment is out of service or for temporary changes. However, in the case of a RIPE application, the proposed change will become the permanent plant configuration if the LAR is approved. Therefore, only long-term actions to reduce risk associated with the new configuration should be considered, such as permanent procedure changes or Page 16 of 18
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests simple plant modifications. For example, if an automatic interlock is defeated permanently, procedure changes to verify proper manual operation of the equipment may be appropriate to reduce the risk associated with removal of the automatic interlock.
4.3.5. Additional Considerations Ensure the issue is well-defined: Confirm that the specific issue is appropriately defined and articulated in order to illustrate the safety impact due to the issue.
Realism so as to not bias the assessments: The level of realism and analyses will vary depending on the issue, but in order to avoid bias, realistic analysis is the objective. The licenses assessment should include sensitivity analyses to address the key assumptions and sources of uncertainty that are driving the results. If the risk impact is exceedingly small, or clearly large, then a bounding evaluation may suffice.
Uncertainty considerations: Sensitivity analysis should be performed, commensurate with the impact of the issue, to address any key assumptions and sources of uncertainty that may influence the results.
Evaluation of the overall nature of the risk impact of a potential action:
Both beneficial and adverse effects should be considered (e.g.,
replacing a small pump with a large pump could reduce the available margin of an emergency diesel generator, or closing and depowering pressurizer power operated relief valve block valves to prevent spurious operation could reduce effectiveness of feed and bleed operations).
Identifying the extent of the impact: The specific intended impact of the issue, as well as other related or indirect effects, should be addressed (e.g., FLEX provides mitigation for more than external hazards even though that is its fundamental intended purpose). In other words, one specific issue could impact the specific function under consideration as well as multiple other separate plant functions. This could include both positive and negative impacts that may not be immediately evident if the impacts of the issue are considered independently.
4.4. Emergency Plans (Replacement for LIC-101, Revision 6, Appendix B, Section 9.0, Amendments for Emergency Plan Changes)
RIPE is not applicable to any issues for which the safety impact cannot be directly assessed using PRA. Therefore, LARs related to the emergency plans will not be considered for NRC review under the RIPE streamlined LAR review process.
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Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests 4.5    Security-Related Amendments (Supplement to LIC-101, Revision 6, Appendix B)
RIPE is not applicable to any issues for which the safety impact cannot be directly assessed using PRA. Therefore, LARs related to the security program will not be considered for NRC review under the RIPE streamlined LAR review process.
4.6    Fuel Related Documents RIPE is not applicable to issues related to changes in reactor fuel that cannot be directly assessed using PRA. Therefore, LARs related to the fuel changes will not be considered for NRC review under the RIPE streamlined LAR review process.
4.7    Technical Specification Amendments The RIPE streamlined review process is not applicable to Technical Specification LARs.
: 5. PAPERWORK REDUCTION ACT 5.1    Paperwork Reduction Act This document references voluntary guidance for implementing the mandatory information collections in 10 CFR Part 50 that are subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et. seq.). These information collections were approved by the Office of Management and Budget (OMB), under control number 3150-0011. Send comments regarding this information collection to the FOIA, Library, and Information Collections Branch, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to Infocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202 (3150-0011), Office of Management and Budget, Washington, DC 20503.
5.2    Public Protection Notification The NRC may not conduct or sponsor, and a person is not required to respond to, a collection of information unless the document requesting or requiring the collection displays a currently valid OMB control number.
: 6. CONGRESSIONAL REVIEW ACT This temporary staff guidance is a rule as defined in the Congressional Review Act (5 U.S.C. 801-808). However, the Office of Management and Budget has not found it to be a major rule as defined in the Congressional Review Act.
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