ML23248A129
| ML23248A129 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 06/29/2023 |
| From: | Michael Mahoney NRC/NRR/DORL/LPL2-2 |
| To: | Phillabaum J Florida Power & Light Co |
| References | |
| L-2022-LLA-0128 | |
| Download: ML23248A129 (12) | |
Text
From:
Michael Mahoney Sent:
Thursday, June 29, 2023 11:46 AM To:
Phillabaum, Jerry Cc:
Falkiewicz, Timothy
Subject:
St Lucie 50.69 - Additional Audit Questions Attachments:
St. Lucie 50.69 Audit Questions.docx Hi Jerry, The staff has reviewed the information posted in Certrec in response to the audit plan sent on May 17, 2023 (ADAMS Accession ML23137A094).
Attached is the first set of NRC staff audit questions. Please post the responses (or request documents) for the questions to the Certrec Portal as they are completed.
We look forward to discussing these questions and FPL draft responses during the virtual audit currently scheduled for July 20 to 21, 2023. Please contact me at any time prior if a clarification discussion is needed.
Thanks Mike Mahoney Project Manager, LPL2-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Desk: (301)-415-3867 Mobile: (301)-250-0450 Email: Michael.Mahoney@nrc.gov
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AUDIT QUESTIONS LICENSE AMENDMENT REQUEST TO ADOPT 10 CFR 50.69, RISK-INFORMED CATEGORIZATION AND TREATMENT OF STRUCTURES, SYSTEMS, AND COMPONENTS FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT, UNITS 1 AND 2 DOCKET NOS. 50-335 AND 389 APLA Audit Question 01 - Credit for FLEX Equipment and Actions NRC memorandum dated May 6, 20221 provides the NRCs staff updated assessment of identified challenges and strategies for incorporating Diverse and Flexible Mitigation Capability (FLEX) equipment into a PRA model in support of risk-informed decisionmaking in accordance with the guidance of RG 1.2002.
With regards to equipment failure probability, in the memorandum dated May 6, 2022, the NRC staff states in Conclusion 4:
Licensees that choose not to use the generic failure probabilities in PWROG-10842 to develop plant-specific failure probabilities for portable FLEX equipment modeled in PRA used for risk-informed applications should submit a justification for the methods and probabilities used to the NRC for review and approval.
With regards to the uncertainty related to equipment failure probabilities, in the updated NRC memorandum, the NRC staff states in Conclusion 8:
PWROG-18043, Revision 1, notes that there was insufficient data to quantify the failure to load probabilities for portable diesel generators due to lack of detailed data. To account for the uncertainty in the testing activitieslicensees should ensure their preventive maintenance strategies include such testing and that the data reported provides this information. licensees should continue to assess the uncertainty in equipment failure rates and address or disposition it.
With regards to HRA, in the memorandum dated May 6, 2022, the NRC staff states, in part, in Conclusion 11:
EPRI 3002013018 provides updated detailed industry guidance for estimating the human error probabilities (HEPs) of the actions needed to implement mitigating strategies using portable equipment. EPRI 3002013018 provides guidance that is acceptable to the NRC, with the clarifications below...
1 U.S. NRC memorandum, Updated Assessment of Industry Guidance for Crediting Mitigating Strategies in Risk Assessments, dated May 6, 2022 (ADAMS Accession No. ML22014A084).
2 U.S. Nuclear Regulatory Commission, Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities, RG 1.200, Revision 3, December 2020 (ADAMS Accession No. ML20238B871).
With regards to PRA Upgrade, the staff states in the update memorandum in Conclusion 2:
Therefore, Conclusion 2 remains unchanged [that] for any new risk-informed application that has incorporated mitigating strategiesthe licensee should either perform a focused-scope peer review of the PRA model or demonstrate [that it does not meet the three criteria of an PRA Upgrade].
It is unclear to the NRC staff if the St. Lucie PRA models incorporate FLEX equipment and mitigation strategies in the PRA models used for this application.
a) Clarify if the St. Lucie PRA models credit FLEX. If FLEX is credited, then respond to the following parts.
b) Describe the methodology used to assess the failure probabilities of any modeled equipment credited in the licensee's mitigating strategies (i.e., FLEX). The discussion should include a justification of the rationale for parameter values, and how the uncertainties associated with the parameter values are considered in the categorization process in accordance with ASME/ANS RA-Sa-20093, as endorsed by RG 1.200 (e.g., supporting requirements for HLR-DA-D).
c) A discussion detailing the methodology used to assess operator actions related to FLEX equipment and the licensee personnel that perform these actions. The discussion should include:
- i. A summary of how the licensee evaluated the impact of the NRC clarification with regards in using the EPRI 3002013018 FLEX HRA methodology.
ii. Provide updated FLEX HRA results, if required, to address the NRC clarifications.
iii. Provide justification that the use of the EPRI FLEX HRA methodology does not meet the definition of an PRA Upgrade as defined by RG 1.200.
-OR-Propose a mechanism to conduct a focused-scope peer review (FSPR) regarding incorporation of the EPRI FLEX HRA method for the St. Lucie PRA models. Include in the mechanism to close out all F&Os that result from the FSPR prior to implementing the categorization process.
3 American Society of Mechanical Engineers (ASME) and American Nuclear Society (ANS) PRA standard ASME/ANS RA-Sa-2009, "Addenda to ASME/ANS RA-S-2008, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications", February 2009, New York, NY (Copyright).
d) Provide an assessment, such as a sensitivity study, of the impact risk from the uncertainty in FLEX equipment failure rates credited in St. Lucies PRA models.
This assessment should include, if required, any modifications to FLEX modeling based on the issues raised in this question. Include in this discussion the impact of uncertainty in FLEX equipment failure rates on the categorization process.
APLA Audit Question 02 - Open Phase Condition Section C.1.4 of RG 1.200 states the base (e.g., Model of Record) PRA is to represent the as-built, as-operated plant to the extent needed to support the application. The licensee is to have a process that identifies updated plant information that necessitate changes to the base PRA model.
In response to the January 30, 2012, Open Phase Condition (OPC) event at the Byron Station, the NRC issued Bulletin 2012-014. As part of the initial Voluntary Industry Initiative (VII) for mitigation of the potential for the occurrence of an OPC in electrical switchyards5,,licensees have made the addition of an Open Phase Isolation System (OPIS). In accordance with Staff Requirements Memorandum (SRM)-SECY-16-00686, the NRC staff was directed to ensure that licensees have appropriately implemented OPIS, and that licensing bases have been updated accordingly. From the revised voluntary initiative7 and the resulting industry guidance in NEI 19-028 on estimating the risk associated with an OPC and OPIS risk, it is understood that the risk impact of an OPC can vary widely, depending on electrical switchyard configuration and design.
In light of this observation, provide the following information:
a) A discussion of the impact on risk of the OPC issue at St. Lucie, Units 1 and 2.
b) Discuss whether modelling of the OPC issue and any OPIS that has been installed and implemented at St, Lucie have been, or are planned to be, incorporated as part of the plant MOR. If so, provide the following:
ii. The impact, if any, to key assumptions and sources of uncertainty.
iii. A discussion of the HRA methods and assumptions used for OPIS alarm manual response.
iv. The impact to external events (e.g., fire, seismic, flooding, high winds, tornado, other external events, etc.).
- v. A discussion of the risk impact of inadvertent OPIS actuation and justification for 4 U.S. NRC Bulletin 2012-01, Design Vulnerability in Electric Power System (ML12074A115).
5 Anthony R. Pietrangelo to Mark A. Satorius, Ltr re: Industry Initiative on Open Phase Condition - Functioning of Important-to-Safety Structures, Systems and Components (SSCs), dated October 9, 2013 (ML13333A147).
6 U.S. NRC SRM-SECY-16-0068, Interim Enforcement Policy for Open Phase Conditions in Electric Power Systems for Operating Reactors, dated March 9, 2017 (ML17068A297).
7 Doug True to Ho Nieh, Ltr re: Industry Initiative on Open Phase Condition, Revision 3, dated June 6, 2019 (ML19163A176).
8 Nuclear Energy Institute (NEI) 19-02, Guidance for Assessing Open Phase Condition Implementation Using Risk Insights, Revision 0, April 2019 (ML19122A321).
its exclusion.
c) If OPC and OPIS are not planned to be included in the MOR, provide justification why the risk impact is not included by performing either a qualitative or sensitivity analysis.
APLA Audit Question 03 - Determination of Key Sources of Uncertainty for the 10CFR50.69 Categorization Process and Sensitivity Results Sections 50.69(c)(1)(i) and 50.69(c)(1)(ii) of 10 CFR 50.69 require that a licensees PRA be of sufficient quality and level of detail to support the SSC categorization process, and that all aspects of the integrated, systematic process used to characterize SSC importance must reasonably reflect the current plant configuration and operating practices, and applicable plant and industry operational experience. The guidance in NEI 00-04 specifies that sensitivity studies be conducted for each PRA model to address uncertainty. The sensitivity studies are performed to ensure that assumptions and sources of uncertainty (e.g., human error, common cause failure, and maintenance probabilities) do not mask the importance of components. The guidance in NEI 00-04 states that additional applicable sensitivity studies from characterization of PRA adequacy should be considered.
Section 3.2.8 of the LAR Enclosure describes the process used for reviewing the PRA assumptions and sources of uncertainty. The NRC staff reviewed the uncertainty documents provided on this audits electronic portal for the internal events, internal flooding, and fire PRA and found that further clarification is necessary regarding the review of assumptions and sources of uncertainty for this application. It is unclear if additional analysis was performed and documented to determine if any source of uncertainty could adversely impact any SSC categorization. Some portal documents referred to sensitivity studies that are contained in other documents, however these sensitivity results were not provided on the portal. In light of these observations, provide the following information:
a) Provide details of how the PSL PRA sources of uncertainty were evaluated as a potential key source of uncertainty for this application. Include in this discussion any documentation of this process.
b) Provide the results of sensitivity studies that determined the impact on risk for each associated source of uncertainty. Include in this discussion justification that the sensitivity results demonstrate that the associated source of uncertainty does not adversely impact any SSC categorization.
APLA Audit Question 04 - Open F&O CS-B1-01 Concerning Circuit Coordination Regulatory Guide (RG) 1.200, Revision 3 An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-informed Activities, (ADAMS Accession No. ML20238B871), provides guidance for addressing PRA acceptability. RG 1.200 describes a peer review process utilizing the ASME/ANS PRA standard (currently ASME/ANS-RA-Sa-2009) as one acceptable approach for determining the technical adequacy of the PRA once acceptable consensus approaches or models have been established for evaluations that could influence the regulatory decision. The primary results of a peer review are the F&Os recorded by the peer review and the subsequent resolution of these F&Os. A process to close-out Finding-level F&Os is documented in NEI 17-07, Revision 2, Performance of PRA Peer
Reviews Using the ASME/ANS PRA Standard (ADAMS Accession No. ML19231A182) that is endorsed by RG 1.200, Revision 3.
LAR Attachment 3 Disposition and Resolution of Open Peer Review Findings and Self-Assessment Open Items presents a Finding-level F&O (i.e., CS-B1-01) which states:
No evaluation was performed to verify that the new components and cables associated with the Fire PRA is bounded by existing overcurrent coordination analysis.
The St. Lucie disposition for Finding CS-B1-01 states:
This finding has been resolved, but independent review to certify closure has not yet been completed. This has no impact on 10 CFR 50.69 implementation.
LAR Section 3.3 explains that in April 2019, the Pressurized Water Reactor Owners Group performed an independent assessment and certified that all F&Os generated for PSL were closed except for fire-related items in Attachment 3. Since April 2019, it appears there have been efforts to resolve Finding CS-B1-01.
In the file identified as AR for None-Safety Related MCC 1A3 & 1B3 Breaker Coordination.pdf, it is stated that during review of coordination calculation, PSL-1FSE-09-001, it was discovered there were feeder breakers for loads downstream of non-safety related motor control center (MCCs) 1A3 and 1B3 modeled in the fire PRA that were not fully coordinated. Iin another file identified as AR 2318093 Enhance Non-Safety MCC BRKS Coord for the Fire PRA Modeling, it is stated for MCC 1A3 and 1B3 that enough margin exists to shift their current time current characteristics (TCC) to the right without challenging coordination with the upstream load center breakers. This statement appears to indicate that some adjustment is needed to the TCC of these breakers to resolve the coordination issue. It is not completely clear to NRC whether the adjustment has been made to resolve the coordination issue associated with MCC 1A3 and 1B3, which are credited in the PRA, has been resolved.
NRC staff notes that circuit breakers and fuses should be adequately coordinated with the upstream load center breaker over the rated range of the circuit, to prevent the adverse effects of a fault on the rest of the circuits powered from a common source. If circuits modelled in the fire PRA cannot be found to be coordinated, then the coordination issues should be physically resolved, or the negative effects of the coordination issue should be modelled in the fire PRA.
It appears that an evaluation has been performed and was documented in a cited report (i.e.,
PSL-1FSE-09-001) to evaluate whether new components and cables associated with the Fire PRA are bounded by existing overcurrent coordination analysis as requested in Finding CS-B1-
- 01. In the file identified as AR 2318092 NRC TFP1 SR MCCS Potential Lack of Coordination.pdf, it is stated that three generic sources of potential weaknesses in circuit coordination on Unit 1 Safety-Related MCCs were identified but were shown not to be a concern to safe shutdown or impact PRA risk. Accordingly, it appears that Safety-Related MCCs are not a concern but certain non-Safety-Related MCCs are a concern. However, the full scope content of PSL-1FSE-09-001 is not known.
Given the observations above, address the following:
a) Confirm that Finding CS-B1-01 has been closed using an NRC approved F&O closure process,
- OR-Commit to a licensee condition (e.g., an implementation item) that ensures Finding CS-B1-01 will be closed using an NRC approved F&O closure process prior to implementation of the 10 CFR 50.69 risk categorization program.
- OR-Describe the evaluation that was performed to verify that the new (non-safe shutdown) components and cables modeled in the fire PRA are bounded by existing overcurrent coordination analysis. Also, describe actions (if any) performed after the evaluation to ensure circuit coordination. Include in this description:
- i.
Discussion of how the evaluation assures that new (non-safe shutdown) components and cables modeled in the Fire PRA are bounded by existing overcurrent coordination analysis.
ii.
Discussion of the results of the evaluation discussed above.
iii.
If certain circuits were found to uncoordinated by the evaluation, then describe the efforts undertaken that resolve the coordination issue(s), or demonstrate (e.g., through a sensitivity study) that the impact of the coordination issues do not have a consequential impact on 10 CFR 50.69 risk categorization.
APLA Audit Question 05 - Open F&O CS-A3-01 Concerning MSO of Fire PRA Components Regulatory Guide (RG) 1.200, Revision 3 An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-informed Activities, (ADAMS Accession No. ML20238B871), provides guidance for addressing PRA acceptability. RG 1.200 describes a peer review process utilizing the ASME/ANS PRA standard (currently ASME/ANS-RA-Sa-2009) as one acceptable approach for determining the technical adequacy of the PRA once acceptable consensus approaches or models have been established for evaluations that could influence the regulatory decision. The primary results of a peer review are the F&Os recorded by the peer review and the subsequent resolution of these F&Os. A process to close-out Finding-level F&Os is documented in NEI 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard (ADAMS Accession No. ML19231A182) that is endorsed by RG 1.200, Revision 3.
LAR Attachment 3 Disposition and Resolution of Open Peer Review Findings and Self-Assessment Open Items presents a Finding-level F&O (i.e., CS-A3-01) which states:
4kV power and 125VDC control cables required to support the operation of the Containment Spray Pump were not identified. Fire PRA Plant Response model and other Fire PRA support tasks are adversely affected. Perform a comparison of the components identified on the MSO (multiple spurious operation) list against the Fire PRA components for which new cable selection was performed (i.e., components not previously identified on the Appendix R safe shutdown equipment list. Verify that the cable selection for the common components supports all credited operations. Fire PRA Plant Response model and other Fire PRA support tasks are adversely affected.
The St. Lucie disposition for Finding CS-A3-01 states:
This finding has been resolved, but independent review to certify closure has not yet been completed. This has no impact on 10 CFR 50.69 implementation.
Again, LAR Section 3.3 explains that in April 2019, the Pressurized Water Reactor Owners Group performed an independent assessment and certified that all F&Os generated for PSL were closed except for fire-related items in Attachment 3. Since April 2019, it appears there have been efforts to resolve the Finding CS-A3-01.
In license report [PSL-BFJR-16-039, Revision 4] St Lucie NFPA 805 - Task 2 Component and Cable Selection, dated August 24, 2020, it is explained that to address Multiple Spurious Operations (MSO) for the fire PRA a review using an expert panel process is performed to identify and characterize potential MSO combinations that lead to new accident sequences. In license report [FPL-SL120-PR-001], Update Review for St. Units 1 and 2 Cable-to-Fire-to-Compartment Relationships, an MSO designator is a assigned a large fraction of the plant components. However, NRC staff could not conclude after reviewing these two reports that the circuits of concern cited in the Finding had been identified (i.e., 4kV power and 125VDC control cables required to support the operation of the Containment Spray Pump). Moreover, NRC staff could not confirm whether components in the MSO list were compared to the fire PRA component list to identify additional circuits that may need to be selected or ensure that cable selection for common components supports all credited operations. Given the observations above, address the following:
a) Confirm that Finding CS-A3-01 has been closed using an NRC approved F&O closure process,
-OR-Commit to a licensee condition (e.g., an implementation item) that ensures Finding CS-A3-01 will be closed using an NRC approved F&O closure process prior to implementation of the 10 CFR 50.69 risk categorization program.
-OR-Describe the evaluation that was performed to 1) compare the components identified on the MSO list to the fire PRA component list to identify additional circuits that may need to be selected, 2) ensure that cable selection for common components supports all credited operations, and 3) identify the 4kV power and 125VDC control cables required to support the operation of the Containment Spray Pump were identified for the fire PRA.
APLA Audit Question 06 - Status of Fire F&Os Regulatory Guide (RG) 1.200, Revision 3 An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-informed Activities, (ADAMS Accession No. ML20238B871), provides guidance for addressing PRA acceptability. RG 1.200 describes a peer review process utilizing the ASME/ANS PRA standard (currently ASME/ANS-RA-Sa-2009) as one acceptable approach for determining the technical adequacy of the PRA once acceptable consensus approaches or models have been established for evaluations that could influence the regulatory decision. The primary results of a peer review are the F&Os recorded by the peer review and the subsequent resolution of these F&Os. A process to close-
out Finding-level F&Os is documented in NEI 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard (ADAMS Accession No. ML19231A182) that is endorsed by RG 1.200, Revision 3.
The NRC staff reviewed the peer review and closure review documents provided on this audits electronic portal regarding open F&Os and found that further clarification is necessary regarding the status of three fire F&Os. The licensee document [PSL-FJR-17025], regarding the January 2010 fire PRA peer review states in Section 4 and Table 4-15 that a total of thirty-six findings were determined by the review team. The NRC staff notes that the documents [PSL-BFJR 020 and PSL-BFJR-19-005] state that only thirty-three fire PRA findings were reviewed on both occasions. It is unclear to the staff the correct status of the F&Os closed out after the August 2018 re-review.
a) Provide clarification of the F&Os (all models) that were closed out after the August 2018 review.
b) Identify, if any, F&Os that were not assessed as closed by a closure review team.
Include in this discussion the disposition of these F&Os for this application.
APLA Audit Question 07 - Status of PRA Upgrades Associated with F&Os Regulatory Guide (RG) 1.200, Revision 3 An Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-informed Activities, (ADAMS Accession No. ML20238B871), provides guidance for addressing PRA acceptability. RG 1.200 describes a peer review process utilizing the ASME/ANS PRA standard (currently ASME/ANS-RA-Sa-2009) as one acceptable approach for determining the technical adequacy of the PRA once acceptable consensus approaches or models have been established for evaluations that could influence the regulatory decision. The primary results of a peer review are the F&Os recorded by the peer review and the subsequent resolution of these F&Os. A process to close-out Finding-level F&Os is documented in NEI 17-07, Revision 2, Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard (ADAMS Accession No. ML19231A182) that is endorsed by RG 1.200, Revision 3.
The NRC staff reviewed the peer review and closure review documents provided on this audits electronic portal regarding open F&Os and found that further clarification is necessary regarding the disposition of closed F&Os that resulted in PRA Upgrades. The NRC staff notes that the August 2018 closure review [PSL-BFJR-19-005] states that the independent assessment team (IAT) determined that four fire F&Os (F-5, F-6, F-8, and F-24) remain open since the changes to the PRA model to closed them constituted a PRA Upgrade that required a focused-scope peer review (FSPR). The subsequent IAT report [PSL-BFJR-19-024] issued in April 2019 appears to have performed an FSPR on three closed fire F&Os (IGN-A5-01, SF-A1-01, and FSS-H1-01).
However, the April 2019 IAT identified the F-5, F-6, F-8, and F-24 F&Os as PRA Maintenance.
It is unclear to the NRC staff the inconsistency between the two IATS concerning the F-5, F-6, F-8, and F-24 F&Os.
a) Provide clarification of the PRA model change categorization associated with the closure of the F-5, F-6, F-8, and F-24 F&Os. Include in this discussion an explanation on the two different IAT assessments.
b) Propose a mechanism, if any of the four F&Os were determined to be PRA Upgrades, to perform a FSPR and close any associated F&O prior to implementation of the categorization process.
APLC Audit Question 1 - Seismic Tier 1 GMRS vs SSE Criteria Paragraph 50.69(b)(2)(ii) of 10 CFR requires that the measures taken to assure that the quality and level of detail of the systematic processes that evaluate the plant for external events during operation are adequate for the categorization of SSCs.
Section 3.2.3 of the LAR Enclosure references the EPRI 3002017583 Tier 1 criteria for the Ground Motion Response Spectrum (GMRS) of below or approximately equal to the Safe Shutdown Earthquake (SSE) between 1.0 and 10.0 Hertz. The LAR continues by stating that the St. Lucie response to the NRC 50.54(f) letter, regarding post-Fukushima recommendations, concluded that the plant SSE exceeded the GMRS in the specified frequency range. However, the staff notes that no curves showing the SSE and GMRS and their comparison are provided in the LAR.
Provide an SSE/GRMS hazard curve comparison demonstrating that the Tier 1 criteria are met for the appropriate frequency band.
APLC Audit Question 2 - External Hazards Screening In Attachment 4 (External Hazards Screening) of the LAR Enclosure, the licensee states that hurricanes are included as a contributor to the external flooding hazard and high wind hazard.
However, the staff did not identify a discussion of the high wind hazard in Attachment 4.
a) Clarify that hurricanes are meant to be included as a contributor to the extreme wind or tornado hazard listed in Attachment 4.
If yes to a), demonstrate how the Saint Lucies (PSL) hurricane hazard is enveloped by the screening criteria for extreme wind or tornado. Otherwise, add a high wind entry to Attachment 4, address its screening criteria, and demonstrate how hurricanes are enveloped by high winds.
The staff notes that PSL Units 1 and 2 were evaluated for external hazards as part of its TSTF-505 LAR (ADAMS Accession No. ML14353A016; 2014). Staff also notes that a flood hazard reevaluation report (FHRR) was submitted for PSL Units 1 and 2 (ADAMS Accession No. ML15083A306; 2015).
Paragraph 50.69(b)(2)(ii) of 10 CFR requires that the measures taken to assure that the quality and level of detail of the systematic processes that evaluate the plant for external events during operation are adequate for the categorization of SSCs.
b) Please identify and describe any updates to the evaluations conducted for external flooding, extreme wind, tornado, or hurricane and their implications on the 10 CFR 50.69 categorization of SSCs in PSL Units 1 and 2.
Audit topic for discussion during July 20 to 21, 2023 audit meeting:
PSL-BF-JR-17-056, regarding LAR Attachment 2 risk values, provides two separate tables that have significantly different values (the latter table is provided in the LAR).
Please clarify what each table represents and the reason for the difference in values.