TSG-DORL-2021-01, Temporary Staff Guidance TSG-DORL-2021-01, Revision 1, Risk-Informed Process for Evaluations: Difference between revisions

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{{Adams
#REDIRECT [[TSG-DORL-2021-01, NRR Temporary Staff Guidance - Risk-Informed Process for Evaluations]]
| number = ML21180A013
| issue date = 06/30/2021
| title = Temporary Staff Guidance TSG-DORL-2021-01, Revision 1, Risk-Informed Process for Evaluations
| author name = Reed T, Zoulis A
| author affiliation = NRC/NRR/DORL/LPLIV, NRC/NRR/DRA/APOB
| addressee name =
| addressee affiliation =
| docket =
| license number =
| contact person = Lingam S, NRR/DORL
| document report number = TSG-DORL-2021-01, Rev 1
| package number = ML21180A011
| document type = Guidance Document
| page count = 23
}}
 
=Text=
{{#Wiki_filter:U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation NRR Temporary Staff Guidance Page 1 of 23 Temporary Staff Guidance No.:
TSG-DORL-2021-01 Revision 1 Temporary Staff Guidance
 
==Title:==
RISK-INFORMED PROCESS FOR EVALUATIONS Effective Date:
June 30, 2021 Approved By:
Bo Pham (Jennifer Dixon-Herrity for)
Date Approved:
June 30, 2021 Primary
 
==Contact:==
T. Reed 301-415-1462 Timothy.Reed@nrc.gov Responsible Organization:
NRR/DORL ADAMS Accession No.:
ML21180A013 A. Zoulis 301-415-1209 Antonios.Zoulis@nrc.gov
 
ML21180A013 A. Zoulis 301-415-1209 Antonios.Zoulis@nrc.gov Summary: This revision includes guidance for applying RIPE for licensees with an NRC-approved TSTF-425, Relocate Surveillance Frequencies to Licensee Control-RITSTF Initiative 5b, license amendment ADAMS Accession No. ML21180A013
*by e-mail OFFICE NRR/DORL/LPL4/PM*
NRR/DORL/LPL4/LA*
NRR/DORL/LPL4/BC*
NAME TReed PBlechman JDixon-Herrity (SLee for)
DATE 6/28/21 6/30/21 6/29/21 OFFICE OGC-NLO*
NRR/DORL/D*
NAME KGamin BPham (JDixon-Herrity for)
DATE 6/23/21 6/30/21
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 3 of 23
: 1.
OBJECTIVE This temporary staff guidance (TSG) document provides the Office of Nuclear Reactor Regulation (NRR) staff the framework for streamlined processing of license amendment 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 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 TSG 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 that have a technically acceptable PRA and have established an Integrated Decision-Making Panel (IDP). For the purposes of RIPE, having a technically acceptable PRA must be demonstrated by having an approved and implemented license amendment for Technical Specifications Task Force (TSTF)
Traveler TSTF-505, Provide Risk Informed Extended Completion Times - RITSTF
[Risk-Informed TSTF] Initiative 4b1 or TSTF-425 Relocate Surveillance Frequencies to Licensee Control-RITSTF Initiative 5b. For the purposes of RIPE, an IDP may be established by having an approved and implemented 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, amendment or by establishing 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). Licensees that have implemented an NRC-approved amendment to adopt TSTF-505 or TSTF-425 and have established an IDP 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.
1 NRC has approved some licensee programs for risk-informed initiatives consistent with NEI 06-09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS)
Guidelines and NEI 04-10, Risk-Informed Technical Specifications Initiative 5b, Risk-Informed Method for Control of Surveillance Frequencies, which can be used in lieu of TSTF-505 or TSTF-425, respectively, for RIPE. Any references in this TSG to TSTF-505 and TSTF-425 also include NEI 06-09 and NEI 04-10, respectively.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 4 of 23 RIPE was originally developed for licensees that have an approved and implemented TSTF-505 license amendment. Licensees that use an approved and implemented TSTF-425 license amendment to demonstrate PRA technical acceptability may use the RIPE process to characterize the safety impact of proposed changes by supplementing their submittal with additional information relative to PRA technical acceptability.
Specifically, licensees that rely on their TSTF-425 program for PRA technical acceptability must:
Justify that the issue being analyzed is limited to internal events or identify which additional previously NRC-approved applications address any relevant external hazards (e.g., internal fires, seismic, etc.) beyond internal events. If the issue involves a hazard that is not covered by a previously approved NRC application, the licensee may not use this process.
If the issue involves an external hazard covered by a previously approved NRC application, justify that the associated PRA does not have any applicable open facts and observations (F&Os).
Provide technical justification for the exclusion of external hazards not applicable to the exemption or amendment request.
Describe any open F&Os from the internal events PRA, including an assessment of the relevance, or lack thereof, of the F&O to the decision being sought. In order to support a streamlined NRC review, licensees should make every effort to close F&Os in advance, typically via the finding closure process.
Describe the maintenance process of the PRA model, including any updates, peer reviews, and independent assessments performed since the PRA was reviewed as part of an approved licensing action by the NRC.
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).
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 5 of 23 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)
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 or TSTF-425 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 on the acceptance review to determine if there is no technical objection in applying the RIPE process. No technical objection means that the technical branch has no objection to applying RIPE for the request without additional review in the branch's respective technical area.
This review entails reviewing the request to ensure that the concerns related to the branchs technical area have been considered by the IDP. Any technical
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 6 of 23 objections identified by the branch must be supported by a sound regulatory basis that challenges the safety impact characterization.
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.
RIPE Applicability Review (Supplement to LIC-103, Revision 2, Section 4.2, Review Request for Completeness and Acceptability)
A RIPE applicability review includes both an acceptance review in accordance with LIC-109, Acceptance Review Procedures, as well as the staff determination that there is no technical objection to applying the RIPE process for the submittal, with the additions and exceptions noted below.
The PM, DRA reviewer, EnvCOE reviewer (if required), and the engineering technical reviewer(s) determine concurrently with the acceptance review that they have no technical objection and that they believe 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 technical objection to applying the RIPE process. This includes agreeing with the licensees assumptions in the submitted analysis, agreeing that the licensee has used an appropriate methodology, agreeing that the licensee fully considered the technical aspects of the issue under consideration to support the IDPs determination, and agreeing that the screening questions were answered acceptably by the licensees IDP. See Section 3.3.5 for more details.
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.
The RIPE submittal confirms that the plant has implemented an NRC approved TSTF-505 or TSTF-425 risk-informed license amendment and has completed all associated license conditions.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 7 of 23 If the RIPE submittal relies on a TSTF-425 license amendment to demonstrate PRA acceptability, the submittal includes the following additional information:
o Description of PRA model changes and peer review history since implementation of TSTF-425.
o Description of independent assessment reviews.
o Description of all open F&Os, including a discussion about whether they are applicable to the submittal.
o Description of key assumptions and sources of uncertainty.
o Explanation of external hazard applicability, including Discussion of non-applicable external hazards.
Discussion of applicable external hazards, including the previously NRC-approved application that reviewed the PRA model for the applicable external hazard, and any changes, peer reviews, and open F&O discussions for that model.
The RIPE submittal includes a description of surrogates used in the application.
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 (i.e., risk-informed considering both qualitative and quantitative risk),
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.
o Cumulative risk is assessed on a plant-specific basis, 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 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 have a technical objection and believe 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
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 8 of 23 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 management tool T* = 0 2
PM reviews submittal for information sufficiency
< T = 14 days (2 weeks) 3 Technical staff determines if there is any technical objection in applying the RIPE process and provides recommendation to PM
< T = 14 days (2 weeks) 4 PM notifies licensee or applicant (e.g., via call, e-mail or letter) that the submittal meets the criteria for a streamlined review and is acceptable for review
< T = 21 days (3 weeks) 5 PM records the date of acceptance review notification in the NRR workload management tool
< T = 21 days (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 having review elements clearly and completely addressed in the submittal. In the rare case that an RAI is required, the milestones in Table 3.2, may not be appropriate. If this occurs, the PM in consultation with LPMB (if required) will notify the licensee and develop new work schedule milestones.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 9 of 23 Table 3.2, Project Milestones for a RIPE Exemption without RAIs TECHNICAL REVIEW AND PROCESSING MILESTONES SCHEDULE*
1 DRA exemption review input provided to PM
< T = 49 days (7 weeks) 2 EnvCOE provide environmental review to PM (if required)
< T = 49 days (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 Division Director (or delegate) to sign)
< T = 91 days (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 an IDP RIPE can only be used by and for licensees that have a technically acceptable PRA model and have established an IDP, as discussed in Section 2 of this TSG. RIPE builds on the licensees expanded use of PRA models for making day-to-day decisions and benefits from the use of IDPs that were part of implementation of 10 CFR 50.69 and other initiatives.
The DRA technical reviewer will confirm that the licensee has implemented an IDP consistent with risk-informed initiative 10 CFR 50.69 or equivalent, as discussed in Section 2 of this TSG. The DRA technical reviewer will also 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 the 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 a technically acceptable PRA model in order to leverage its PRA models to perform quantitative risk assessments to
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 10 of 23 support using this process. To do so, the DRA technical reviewer will confirm 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 risk-informed initiative TSTF-505 or TSTF-425 and has completed all associated license conditions.
The licensees PRA model was found acceptable to support a TSTF-505 or TSTF-425 license amendment by the NRC.
If the RIPE submittal relies on a TSTF-425 license amendment to demonstrate PRA acceptability, the technical reviewer must review the following additional information:
o PRA model changes and peer review history since implementation of TSTF-425.
o Independent assessment reviews.
o All open F&Os.
o Key assumptions and sources of uncertainty.
o External hazard applicability, including Discussion of non-applicable external hazards.
Discussion of applicable external hazards, including the previously NRC-approved application that reviewed the PRA model for the applicable external hazard, and any changes, peer reviews, and open F&O discussions for that model.
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 between plant risk with the proposed change and without the proposed change. For compliance issues, the change in risk is the difference between risk if the plant were fully compliant with its licensing basis, and risk with the plant in the non-compliant configuration requested in the submittal. For licensee-identified issues that do not involve a compliance issue, the change in risk is the difference between risk with the plant in the current configuration and with the plant in the configuration requested in the submittal. The risk analysis
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 11 of 23 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.
The issue contributes less than 1 x 10-8/year to LERF.
Cumulative risk is assessed on a plant-specific basis 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.
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, but are encouraged. 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 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,
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 12 of 23 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. The key assumptions, details, and results of the sensitivity studies should be documented for consideration by the GAET or IDP. 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.
The key assumptions, details, and results of the sensitivity studies should be documented for consideration by the GAET or IDP.
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.
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.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 13 of 23 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 (SE) input, including verification that TSTF 505 or TSTF-425 and 10 CFR 50.69 amendments (if used) 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 a 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 or TSTF-425 license amendments. Therefore, one of DRAs PRA branches will be assigned to review a RIPE LAR and will be the lead branch providing an SE 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 on the acceptance review to determine if there is no technical objection in applying the RIPE process. No technical objection means that the technical branch has no objection to applying RIPE for the request without additional review in the branch's respective technical area. This review entails reviewing the request to ensure that the concerns related to the branchs technical area have been considered by the IDP. Any technical objections identified by the branch must be supported by a sound regulatory basis that challenges the safety impact characterization.
An environmental review by the EnvCOE may also be required if the action is not categorically excluded under 10 CFR 51.22(c). See
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 14 of 23 Tables 4.1 and 4.2 in Section 4.1.2 for the creation of the schedule milestones.
4.1.2 RIPE Applicability Review A RIPE applicability review includes both an acceptance review in accordance with LIC-109, Acceptance Review Procedures, as well as the staff determination that there is no technical objection to applying the RIPE process for the submittal, with the following additions and exceptions.
The PM, DRA reviewer, EnvCOE reviewer (if required), and the engineering technical reviewer(s) determine concurrently with the acceptance review that they have no technical objection, and that they believe 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 technical objection to applying the RIPE process. This includes agreeing with the licensees assumptions in the submitted analysis, agreeing that the licensee has used an appropriate methodology, and agreeing that the screening questions were answered acceptably by the licensees IDP. See Section 4.3.5 for more details.
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 or TSTF-425 risk-informed license amendment and has completed all associated license conditions.
If the RIPE submittal relies on a TSTF-425 license amendment to demonstrate PRA acceptability, the submittal includes the following additional information:
o Description of PRA model changes and peer review history since implementation of TSTF-425.
o Description of independent assessment reviews.
o Description of all open F&Os, including a discussion about whether they are applicable to the submittal.
o Description of key assumptions and sources of uncertainty.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 15 of 23 o Explanation of external hazard applicability, including Discussion of non-applicable external hazards.
Discussion of applicable external hazards, including the previously NRC-approved application that reviewed the PRA model for the applicable external hazard, and any changes, peer reviews, and open F&O discussions for that model.
The RIPE submittal includes a description of surrogates used in the application 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.
o Cumulative risk is assessed on a plant-specific basis 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.
If the PM and DRA, environmental and engineering reviewers have a technical objection and believe 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:
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 16 of 23 Table 4.1, Acceptance Review Milestones for a RIPE LAR ACCEPTANCE REVIEW MILESTONES SCHEDULE 1 PM creates project in the NRR workload management tool T* = 0 2 PM reviews submittal for information sufficiency
< T = 14 days (2 weeks) 3 Technical staff determines if there is any technical objection to applying the RIPE process and provides recommendation to PM
< T = 14 days (2 weeks) 4 PM notifies licensee or applicant (e.g., via call, e-mail or letter) that LAR meets the criteria for a streamlined review and is acceptable for review
< T = 21 days (3 weeks) 5 PM records the date of acceptance review notification in the NRR workload management tool
< T = 21 days (3 weeks)
*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 the RIPE limitations and review elements clearly and completely addressed in the submittal. In the rare case that an RAI is required, the milestones in Table 4.2 below may not be appropriate. If this occurs, the PM in consultation with LPMB (if required) will notify the licensee and develop new work schedule milestones.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 17 of 23 Table 4.2, Project Milestones for RIPE LAR without RAIs TECHNICAL REVIEW AND PROCESSING MILESTONES SCHEDULE*
1 PM issues the notice of application in Federal Register
< 42 days (6 weeks) 2 DRA SE input provided to PM
< 70 days (10 weeks) 3 EnvCOE provide environmental review to PM (if required)
< 70 days (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 or TSTF-425 and 10 CFR 50.69 amendments (if used) 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 technically acceptable model.
4.3.1. Implementation of an IDP The RIPE streamlined process can only be used by and for licensees that have a technically acceptable PRA and have established an IDP, as discussed in Section 2 of this TSG. 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.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 18 of 23 The DRA technical reviewer will confirm that the licensee has implemented an IDP consistent with 10 CFR 50.69 or equivalent, as discussed in Section 2 of this TSG. The DRA technical reviewer will also 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 the 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 a technically acceptable PRA model in order to leverage its PRA models to perform quantitative risk assessments to support using this process. To do so, the DRA technical reviewer will confirm 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 risk-informed initiative TSTF-505 or TSTF-425 and has completed all associated license conditions.
The licensees PRA model was found acceptable to support a TSTF-505 or TSTF-425 license amendment by the NRC.
If the RIPE submittal relies on a TSTF-425 license amendment to demonstrate PRA acceptability, the technical reviewer must review the following additional information:
o PRA model changes and peer review history since implementation of TSTF-425.
o Independent assessment reviews.
o All open F&Os.
o Key assumptions and sources of uncertainty.
o External hazard applicability, including Discussion of non-applicable external hazards.
Discussion of applicable external hazards, including the previously NRC-approved application that reviewed the PRA model for the applicable external hazard, and any changes, peer reviews, and open F&O discussions for that model.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 19 of 23 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., external events, 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. For compliance issues, the change in risk is the difference between risk if the plant were fully compliant with its licensing basis, and risk with the plant in the non-compliant configuration requested in the submittal. For licensee-identified issues that do not involve a compliance issue, the change in risk is the difference between risk with the plant in the current configuration and with the plant in the configuration requested in the submittal. 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.
The issue contributes less than 1 x 10-8/year to LERF.
Cumulative risk is assessed on a plant-specific basis 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.
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, but are encouraged. However, if the issue was determined to have a minimal impact on safety, then
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 20 of 23 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 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. The key assumptions, details, and results of the sensitivity studies should be documented for consideration by the GAET or IDP. 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.
The key assumptions, details, and results of the sensitivity studies should be documented for consideration by the GAET or IDP.
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.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 21 of 23 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.
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.
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 22 of 23
 
==Enclosure:==
: 1. Appendix A: Change History
 
Temporary Staff Guidance - RIPE Related Exemption and License Amendment Requests Page 23 of 23 Appendix A - Change History TSG Change History - Page 1 of 1 Date Description of Changes Method Used to Announce &
Distribute Training 1/5/21 This is the initial issuance of TSG-DORL-2021-01 for using RIPE E-mail to NRR staff Recommended reading for DORL PMs and technical staff supporting license amendments and exemptions 6/30/21 Revised TSG to include guidance for applying RIPE for licensees with an NRC-approved TSTF-425, Relocate Surveillance Frequencies to Licensee Control-RITSTF Initiative 5b, license amendment E-mail to NRR staff Recommended reading for DORL PMs and technical staff supporting license amendments and exemptions}}

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