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| {{#Wiki_filter:DRAFT - UNCERTIFIED INFORMATIONDRAFT - UNCERTIFIED INFORMATIONPage1 of3QuestionRAI B.1.21-2 (Flow-Accelerated Corrosion)BackgroundFor the "detection of aging effects" program element, Section 4.8 of RBS EP 15 00007 cites procedure EN-DC-315, "Flow-Accelerated Corrosion [FAC] Program," as the basis for being consistent with the GALL ReportAMP XI.M17. Procedure EN-DC-315 states that specific software programs (i.e., "CHECWORKS" and "FACManager Web Edition") shall be used in determining the remaining component life. Based on discussionsduring the AMP Audit breakout session, both software programs are classified as Level C, which does notrequire verification/validation activities. GALL Report AMP XI.M17 states that the FAC program is described inNSAC-202L and that components are suitable for continued service if the predicted wall thickness at the nextscheduled inspection is greater than or equal to the minimum allowable wall thickness. NSAC-202L, Section 2,"Elements of an Effective FAC Program," provides recommendations for ensuring that appropriate qualityassurance is applied, including properly documenting work. Entergy report EC-0000072133, "RF-19 Post-Outage Report," includes a signed output sheet from FAC Manager, which contains wall thickness data andthe measured wear rate from each inspection.IssueFor safety-related components, it is not clear to the staff that the remaining component life is being properlydetermined because the wear rate values are taken from Level C software (i.e., "CHECWORKS" and "FACManager Web Edition"), which does not require validation and verification activities. Although the FACManager output sheets are signed as prepared and verified, the determination of the wear rate values cannotbe independently verified based on the information provided.RequestProvide additional information to show that appropriate quality assurance has been applied to the calculatedwear rates used in the determination of the schedule for inspection of safety-related components.ResponseNote: A previous response to RAI B.1.21-2 was submitted in letter RBG-47834, dated March 8, 2018.The following response is the same as the response in letter RBG-47834 except additional informationregarding software validation has been provided in the 3rd paragraph below. The following responsesupersedes the previous response submitted in letter RBG-47834.CHECWORKS and FAC Manager Web Edition (FMWE) are Level C software which is used for day-to-daysupport activities and whose loss or failure would not affect the immediate ability to operate the plant but couldthreaten the plant's long-term ability to operate. The Level C classification is appropriate because the softwareis not embedded in or integral to a safety-related (SR) structure, system or component (SSC), is not utilized inthe design process of SR SSCs, is not embedded in or an integral part of a non-safety related (NSR) SSCused to support or maintain an important to safety SSC (e.g. surveillance, calibration, post-maintenance test),is not used to determine Technical Specification, NRC regulation/commitments or 10CFR50 compliance, and is DRAFT - UNCERTIFIED INFORMATIONDRAFT - UNCERTIFIED INFORMATIONPage2 of3not used to calibrate or maintain maintenance and test equipment (M&TE) used on safety-related or TechnicalSpecification SSCs.Level C software does not require "verification," which consists of evaluating and analyzing products of eachlife cycle phase (e.g., requirements specification, design descriptions, code, and databases) through testingand reviews or audits to discover and correct deficiencies as early as possible. However, the CHECWORKScode was developed in accordance with the quality assurance policies of EPRI, which require a formalsoftware plan and detailed program documentation. These policies also mandate that a list of program bugs bemaintained. The FMWE code was developed in accordance with the quality assurance policies of Altran, whichalso require a formal testing plan, detailed program documentation, and a list of program bugs.Level C software does require "validation," which is the final testing activity and ensures that the softwareinstallation and integration into the production environment is successful. The installation is performed inaccordance with a documented plan or vendor instructions which may include sample program inputs andoutputs for use in verifying installation. In accordance with the Entergy software quality assurance procedure,each time CHECWORKS or FMWE is revised, FAC personnel validate the revised software using test casesand test databases before the software is placed in production mode. The validation tests provide theappropriate quality assurance to ensure that component wear, wear rate, predicted thickness, and remainingservice life are calculated consistently with NSAC-202L.Predictive model CHECWORKS is just one of the tools used to determine inspection eligibility and priority.Selection of inspection locations for an outage is based on the following factors.previous inspection resultsCHECWORKS susceptibility rankingindustry and plant-specific operating experiencecomponents selected to calibrate CHECWORKScomponents subject to off normal flow conditions, such as caused by a leaking valvesusceptible non-modeled small bore piping that has not been inspectedMeasurement of actual wall thickness during inspections is the primary tool used in the FAC Program todetermine component wear. The measured wall thickness is used to determine wear rates, predictedthickness, and remaining service life in FAC Manager Web Edition (FMWE) according to the following steps.Initial thickness of a component is determined by ultrasonic inspection prior to the component beingplaced in service or in the first ultrasonic inspection during its service life. If an examination has notpreviously been performed on the component, the initial thickness is determined by reviewing the initialultrasonic data for that component. The area of maximum wall thickness within the same region as theworn area is identified. If the thickness is greater than the nominal component wall thickness, themaximum wall thickness within the relevant area is used as the initial thickness. If that thickness is lessthan the nominal wall thickness, the nominal wall thickness is used as the initial thickness.The projected wear rate is calculated by dividing the wear by the time between measurements or thetime between when the component was placed in service and the time of the measurement. Wear isthe amount of material removed or lost from a components wall thickness since baseline or subsequentto being placed in service and time is theactual plant operating hours, although calendar hours may beused for conservatism. | | {{#Wiki_filter:DRAFT - UNCERTIFIED INFORMATION Question RAI B.1.21-2 (Flow-Accelerated Corrosion) |
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| DRAFT - UNCERTIFIED INFORMATIONDRAFT - UNCERTIFIED INFORMATIONPage3 of3The remaining service life (RSL) is determined by subtracting the minimum acceptable wall thicknessfrom the actual measured wall thickness, then dividing by the wear rate times a safety factor of 1.1.If the RSL of a component is greater than or equal to the number of hours in the next operating cycle,the component may be returned to service.If the component's RSL is greater than the number of hoursin the next operating cycle but is less than the number of hours in the next two operating cycles, thecomponent should be considered for re-inspection, repair or replacement during the next scheduledoutage. If the component is acceptable for continued service, it shall be re-examined before, or duringthe cycle during which it is projected to wear to the minimum acceptable wall thickness.Evaluation of wear rates, predicted thickness, and remaining service life is documented and reviewed byqualified FAC personnel or designated personnel qualified in accordance with the engineering calculationprocess. Therefore, appropriate quality assurance is applied to the calculated wear rates used in thedetermination of the schedule for inspection of safety-related components. | | ===Background=== |
| }} | | For the detection of aging effects program element, Section 4.8 of RBS EP 15 00007 cites procedure EN-DC-315, Flow-Accelerated Corrosion [FAC] Program, as the basis for being consistent with the GALL Report AMP XI.M17. Procedure EN-DC-315 states that specific software programs (i.e., CHECWORKS and FAC Manager Web Edition) shall be used in determining the remaining component life. Based on discussions during the AMP Audit breakout session, both software programs are classified as Level C, which does not require verification/validation activities. GALL Report AMP XI.M17 states that the FAC program is described in NSAC-202L and that components are suitable for continued service if the predicted wall thickness at the next scheduled inspection is greater than or equal to the minimum allowable wall thickness. NSAC-202L, Section 2, Elements of an Effective FAC Program, provides recommendations for ensuring that appropriate quality assurance is applied, including properly documenting work. Entergy report EC-0000072133, RF-19 Post-Outage Report, includes a signed output sheet from FAC Manager, which contains wall thickness data and the measured wear rate from each inspection. |
| | Issue For safety-related components, it is not clear to the staff that the remaining component life is being properly determined because the wear rate values are taken from Level C software (i.e., CHECWORKS and FAC Manager Web Edition), which does not require validation and verification activities. Although the FAC Manager output sheets are signed as prepared and verified, the determination of the wear rate values cannot be independently verified based on the information provided. |
| | Request Provide additional information to show that appropriate quality assurance has been applied to the calculated wear rates used in the determination of the schedule for inspection of safety-related components. |
| | |
| | ===Response=== |
| | Note: A previous response to RAI B.1.21-2 was submitted in letter RBG-47834, dated March 8, 2018. |
| | The following response is the same as the response in letter RBG-47834 except additional information regarding software validation has been provided in the 3rd paragraph below. The following response supersedes the previous response submitted in letter RBG-47834. |
| | CHECWORKS and FAC Manager Web Edition (FMWE) are Level C software which is used for day-to-day support activities and whose loss or failure would not affect the immediate ability to operate the plant but could threaten the plants long-term ability to operate. The Level C classification is appropriate because the software is not embedded in or integral to a safety-related (SR) structure, system or component (SSC), is not utilized in the design process of SR SSCs, is not embedded in or an integral part of a non-safety related (NSR) SSC used to support or maintain an important to safety SSC (e.g. surveillance, calibration, post-maintenance test), |
| | is not used to determine Technical Specification, NRC regulation/commitments or 10CFR50 compliance, and is DRAFT - UNCERTIFIED INFORMATION Page 1 of 3 |
| | |
| | DRAFT - UNCERTIFIED INFORMATION not used to calibrate or maintain maintenance and test equipment (M&TE) used on safety-related or Technical Specification SSCs. |
| | Level C software does not require verification, which consists of evaluating and analyzing products of each life cycle phase (e.g., requirements specification, design descriptions, code, and databases) through testing and reviews or audits to discover and correct deficiencies as early as possible. However, the CHECWORKS code was developed in accordance with the quality assurance policies of EPRI, which require a formal software plan and detailed program documentation. These policies also mandate that a list of program bugs be maintained. The FMWE code was developed in accordance with the quality assurance policies of Altran, which also require a formal testing plan, detailed program documentation, and a list of program bugs. |
| | Level C software does require validation, which is the final testing activity and ensures that the software installation and integration into the production environment is successful. The installation is performed in accordance with a documented plan or vendor instructions which may include sample program inputs and outputs for use in verifying installation. In accordance with the Entergy software quality assurance procedure, each time CHECWORKS or FMWE is revised, FAC personnel validate the revised software using test cases and test databases before the software is placed in production mode. The validation tests provide the appropriate quality assurance to ensure that component wear, wear rate, predicted thickness, and remaining service life are calculated consistently with NSAC-202L. |
| | Predictive model CHECWORKS is just one of the tools used to determine inspection eligibility and priority. |
| | Selection of inspection locations for an outage is based on the following factors. |
| | * previous inspection results |
| | * CHECWORKS susceptibility ranking |
| | * industry and plant-specific operating experience |
| | * components selected to calibrate CHECWORKS |
| | * components subject to off normal flow conditions, such as caused by a leaking valve |
| | * susceptible non-modeled small bore piping that has not been inspected Measurement of actual wall thickness during inspections is the primary tool used in the FAC Program to determine component wear. The measured wall thickness is used to determine wear rates, predicted thickness, and remaining service life in FAC Manager Web Edition (FMWE) according to the following steps. |
| | * Initial thickness of a component is determined by ultrasonic inspection prior to the component being placed in service or in the first ultrasonic inspection during its service life. If an examination has not previously been performed on the component, the initial thickness is determined by reviewing the initial ultrasonic data for that component. The area of maximum wall thickness within the same region as the worn area is identified. If the thickness is greater than the nominal component wall thickness, the maximum wall thickness within the relevant area is used as the initial thickness. If that thickness is less than the nominal wall thickness, the nominal wall thickness is used as the initial thickness. |
| | * The projected wear rate is calculated by dividing the wear by the time between measurements or the time between when the component was placed in service and the time of the measurement. Wear is the amount of material removed or lost from a components wall thickness since baseline or subsequent to being placed in service and time is the actual plant operating hours, although calendar hours may be used for conservatism. |
| | DRAFT - UNCERTIFIED INFORMATION Page 2 of 3 |
| | |
| | DRAFT - UNCERTIFIED INFORMATION |
| | * The remaining service life (RSL) is determined by subtracting the minimum acceptable wall thickness from the actual measured wall thickness, then dividing by the wear rate times a safety factor of 1.1. |
| | * If the RSL of a component is greater than or equal to the number of hours in the next operating cycle, the component may be returned to service. If the component's RSL is greater than the number of hours in the next operating cycle but is less than the number of hours in the next two operating cycles, the component should be considered for re-inspection, repair or replacement during the next scheduled outage. If the component is acceptable for continued service, it shall be re-examined before, or during the cycle during which it is projected to wear to the minimum acceptable wall thickness. |
| | Evaluation of wear rates, predicted thickness, and remaining service life is documented and reviewed by qualified FAC personnel or designated personnel qualified in accordance with the engineering calculation process. Therefore, appropriate quality assurance is applied to the calculated wear rates used in the determination of the schedule for inspection of safety-related components. |
| | DRAFT - UNCERTIFIED INFORMATION Page 3 of 3}} |
Letter Sequence Request |
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|
Initiation
- Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request, Request
- Acceptance
- Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement, Supplement
|
MONTHYEARRBG-47805, Response to License Renewal Application NRC Request for Additional Information Set 22017-12-12012 December 2017
Response to License Renewal Application NRC Request for Additional Information Set 2
Project stage: Request
RBG-47807, Response to License Renewal Application NRC Requests for Additional Information Set 32018-01-10010 January 2018
Response to License Renewal Application NRC Requests for Additional Information Set 3
Project stage: Other
RBG-47812, Response to License Renewal Application (LRA) NRC Request for Additional Information (RAI) Set 42018-01-24024 January 2018
Response to License Renewal Application (LRA) NRC Request for Additional Information (RAI) Set 4
Project stage: Request
RBG-47813, Response to License Renewal Application (LRA) NRC Request for Additional Information Set 52018-01-24024 January 2018
Response to License Renewal Application (LRA) NRC Request for Additional Information Set 5
Project stage: Request
RBG-47830, License Renewal Application Update - Neutron Absorbing Material Monitoring Program2018-02-15015 February 2018
License Renewal Application Update - Neutron Absorbing Material Monitoring Program
Project stage: Other
RBG-47828, Response to License Renewal Application NRC Request for Additional Information (RAI) Set 82018-02-20020 February 2018
Response to License Renewal Application NRC Request for Additional Information (RAI) Set 8
Project stage: Request
RBG-47840, Request for Due Date Extension for License Renewal Application NRC Request for Additional Information from 30 Days to 45 Days2018-02-22022 February 2018
Request for Due Date Extension for License Renewal Application NRC Request for Additional Information from 30 Days to 45 Days
Project stage: Request
RBG-47819, Response to License Renewal Application NRC Request for Additional Information - Set 7 Supplement to RAI B.1.11-2a2018-02-26026 February 2018
Response to License Renewal Application NRC Request for Additional Information - Set 7 Supplement to RAI B.1.11-2a
Project stage: Supplement
RBG-47834, Response to License Renewal Application NRC Request for Additional Information (RAI) Set 92018-03-0808 March 2018
Response to License Renewal Application NRC Request for Additional Information (RAI) Set 9
Project stage: Request
RBG-47842, Response to License Renewal Application NRC Request for Additional Information Set 5 Supplement2018-03-22022 March 2018
Response to License Renewal Application NRC Request for Additional Information Set 5 Supplement
Project stage: Supplement
RBG-47848, License Renewal Application Update - Neutron Absorbing Material Monitoring Program - Supplement2018-03-22022 March 2018
License Renewal Application Update - Neutron Absorbing Material Monitoring Program - Supplement
Project stage: Supplement
RBG-47835, Submittal of Response to License Renewal Application NRC Request for Additional Information Set 102018-03-26026 March 2018
Submittal of Response to License Renewal Application NRC Request for Additional Information Set 10
Project stage: Request
RBG-47849, Response to License Renewal Application NRC Request for Additional Information Set 4 Supplement2018-03-27027 March 2018
Response to License Renewal Application NRC Request for Additional Information Set 4 Supplement
Project stage: Supplement
RBG-47846, Response to License Renewal Application NRC Request for Additional Information (RAI) Set 122018-04-0303 April 2018
Response to License Renewal Application NRC Request for Additional Information (RAI) Set 12
Project stage: Request
RBG-47850, Response to License Renewal Application NRC Request for Additional Information Set 5 Supplement2018-04-0404 April 2018
Response to License Renewal Application NRC Request for Additional Information Set 5 Supplement
Project stage: Supplement
ML18099A2362018-04-0909 April 2018
Topics for the April 10, 2018 Public Call with Entergy on River Bend Station, Unit 1 License Renewal Application
Project stage: Meeting
ML18106A6152018-04-16016 April 2018
Topics for the April 18, 2018, Telephone Call - Rev 1 with Aaron'S Rewrite
Project stage: Request
ML18115A0612018-04-25025 April 2018
Draft Response on RAI B1.21-1 Flow Accelerated Corrosion
Project stage: Request
ML18115A0722018-04-25025 April 2018
Draft Response on RAI B.1.25-1(Internal Surfaces in Miscellaneous Piping and Ducting Components)
Project stage: Request
ML18115A1632018-04-25025 April 2018
Draft Response on RBS LRA RAI B.1.21-2 Flow Accelerated Corrosion
Project stage: Request
RBG-47853, Response to License Renewal Application NRC Request for Additional Information Supplement to B.1.35-12018-04-26026 April 2018
Response to License Renewal Application NRC Request for Additional Information Supplement to B.1.35-1
Project stage: Supplement
ML18121A3022018-05-0101 May 2018
Draft Response to NRC Request for Additional Information (RAI) 4.6-2a Generated from Staff'S Review on the River Bend License Renewal Application
Project stage: Draft RAI
ML18121A2942018-05-0101 May 2018
Draft Response to NRC Request for Additional Information (RAI) 4.6-1a Generated from Staffs Review on the River Bend License Renewal Application
Project stage: Draft RAI
ML18122A1262018-05-0202 May 2018
RAI B.1.17-1 Revised - w- header-footer-watermark
Project stage: Request
ML18122A2312018-05-0202 May 2018
Draft Response to NRC Request for Additional Information (RAI) B.1.40-5 Service Water Integrity Generated from Staffs Review on the River Bend Station, Unit 1 License Renewal Application
Project stage: Draft RAI
RBG-47852, Response to License Renewal Application NRC Request for Additional Information Set 132018-05-10010 May 2018
Response to License Renewal Application NRC Request for Additional Information Set 13
Project stage: Request
RBG-47860, Response to License Renewal Application NRC Request for Supplemental Information2018-05-10010 May 2018
Response to License Renewal Application NRC Request for Supplemental Information
Project stage: Supplement
ML18131A2412018-05-11011 May 2018
RBS 012 Item 158a Response (RAI 3.2.2.3.2-1a) Revised - Received on 05/10/2018
Project stage: Request
ML18135A1072018-05-15015 May 2018
RBS Draft Response (RAI 4.3.1-2a_Class 1 Fatigue w-header-footer-watermark_received on 051318
Project stage: Request
ML18136A8212018-05-16016 May 2018
Draft Response to RAI 3.6.2.2.2.2-1a High Voltage Insulators - RBS LRA Review
Project stage: Request
ML18136A7052018-05-16016 May 2018
RBS Draft Response to LRA Review RAI 4.7.3-1a Fluence Effects for Rv Internals
Project stage: Request
RBG-47867, Response to License Renewal Application NRC Request for Additional Information RAI 3.2.2.2-1a Supplement2018-05-16016 May 2018
Response to License Renewal Application NRC Request for Additional Information RAI 3.2.2.2-1a Supplement
Project stage: Supplement
ML18141A4882018-05-21021 May 2018
Draft Response (RAI 3.6.2.2.2.2-1a) from LRA Review Revised After the May 17, 2018 Call
Project stage: Request
ML18143B6862018-05-24024 May 2018
RBS Draft Response (Operating Experience) to Draft RAI 3-0-5 Received 052318
Project stage: Request
RBG-47861, Response to License Renewal Application NRC Request for Additional Information Sets 14,15 and Operating Experience Review Clarification2018-05-29029 May 2018
Response to License Renewal Application NRC Request for Additional Information Sets 14,15 and Operating Experience Review Clarification
Project stage: Request
ML18143B7362018-05-31031 May 2018
NUREG-1437, Dfc, Supplement 58, Generic Environmental Impact Statement for License Renewal of Nuclear Plants - Supplement 58 - Regarding River Bend Station, Unit 1.
Project stage: Acceptance Review
RBG-47870, License Renewal Application, Revised Updated Safety Analysis Report Supplement, Appendix a, Section A.4, License Renewal Commitment List2018-06-0606 June 2018
License Renewal Application, Revised Updated Safety Analysis Report Supplement, Appendix a, Section A.4, License Renewal Commitment List
Project stage: Supplement
RBG-47873, License Renewal Application, Revised Updated Safety Analysis Report Supplement, Appendix a, Section A.4, License Renewal Commitment List, Revised Commitment 52018-06-13013 June 2018
License Renewal Application, Revised Updated Safety Analysis Report Supplement, Appendix a, Section A.4, License Renewal Commitment List, Revised Commitment 5
Project stage: Supplement
ML18212A1512018-07-31031 July 2018
License Renewal Safety Evaluation Report
Project stage: Approval
RBG-47883, Amendment 1 to License Renewal Application2018-08-0202 August 2018
Amendment 1 to License Renewal Application
Project stage: Other
ML18138A3552018-08-16016 August 2018
Safety Evaluation Report Related to the License Renewal of River Bend Station, Unit 1
Project stage: Approval
ML18283A0822018-10-0909 October 2018
Supplemental Information Related to License Renewal Application NRC Request for Additional Information to Clarify Response to RAI 2.3.3.16-1 Set 11
Project stage: Response to RAI
ML18346A6442018-10-19019 October 2018
Revision to River Bend SER - ML18212A151 - Section 2-3-3-16 Plant Drains
Project stage: Other
2018-04-03
[Table View] |
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Category:Request for Additional Information (RAI)
MONTHYEARML24255A1192024-09-16016 September 2024
Notification of NRC Follow Up Inspection for One Severity Level (SL) III and Two SL IV or Three or More SL IV Violations and Request for Additional Information
ML24106A0432024-04-11011 April 2024
June 2024 Emergency Preparedness Exercise Inspection Request for Information
ML24088A0092024-03-27027 March 2024
NRR E-mail Capture - Entergy Fleet - Final Request for Confirmation of Information (RCI) Re Alternative Request EN-RR-22-001 Concerning ASME Code Case N-752 (L-2022-LLR-0054)
ML23348A1222023-12-14014 December 2023
NRR E-mail Capture - Grand Gulf, River Bend, and Waterford, Unit 3 - 2nd Round of Official RAIs for RR EN-RR-22-001, Use ASME Code Case N-752, Risk Informed Categorization for Class 2 and 3 Systems
ML23311A4322023-11-0909 November 2023
Notification of NRC Supplemental Inspection (95001) and Request for Information
ML23195A0692023-07-24024 July 2023
2023 River Bend Station Notification of Biennial Problem Identification and Resolution Inspection and Request for Information
ML23116A1462023-04-26026 April 2023
NRR E-mail Capture - Entergy Fleet (Grand Gulf and River Bend) - Final RAI for Request to Update ASME Code Relief Request Safety Evaluations with NRC-Approved Revision of BWRVIP Guidelines (GG-ISI-020, and RBS-ISI-019)
ML23081A4602023-03-22022 March 2023
RFI River Bend CETI 2023012 Drr
ML23004A0422023-01-0404 January 2023
License Renewal Phase 1 Request for Information
ML22354A0812022-12-20020 December 2022
Inservice Inspection Request for Information
ML22235A1082022-08-19019 August 2022
RBS Emergency Preparedness (EP) Exercise Inspection October 2022 RFI
ML22180A0612022-06-29029 June 2022
Notification of an NRC Fire Protection Baseline Inspection (NRC Inspection Report 05000458/2022010) and Request for Information
ML20350B8112020-12-11011 December 2020
2021 RBS PIR Request for Information
ML20337A4452020-12-0202 December 2020
Riverbend Station Inservice Inspection Request for Information
ML20255A1892020-09-0909 September 2020
Email 09Sept2020 - RFI for RBS EP Exercise Inspection
ML20260H4422020-09-0808 September 2020
NRR E-mail Capture - Entergy Fleet (Grand Gulf and River Bend) - Official RAIs for RR Associated with Updating ASME Code RR SEs with NRC-Approved Revision of BWRVIP Guidelines (GG-ISI-020 and RBS-ISI-019)
ML20162A1122020-06-10010 June 2020
Notification of Inspection (NRC Inspection Report 05000458/2020003) and Request for Information
ML20126G3922020-05-0101 May 2020
Request for Information, May 01, 2020, River Bend Station Special Inspection, NRC Inspection Report 2020050
ML20038A2092020-02-0404 February 2020
05000458 Request for Information IR2020-001 Occupational Radiation Safety
ML19102A0722019-04-11011 April 2019
NRR E-mail Capture - River Bend Station, Unit 1 - Final Request for Additional Information Relief Request RBS-ISI-021
ML18250A3112018-09-0404 September 2018
NRR E-mail Capture - Final RAI - RBS EAL Scheme Change LAR (L-2018-LLA-0130)
ML18229A0082018-08-16016 August 2018
NRR E-mail Capture - Final Request for Additional Information for P-T Curves - NON-PROPRIETARY Version
ML18250A3102018-08-0101 August 2018
NRR E-mail Capture - Draft RAI - RBS EP EAL Scheme Change LAR (L-2018-LLA-0130)
ML18151A0822018-05-30030 May 2018
Summary of a Telephone Conference Call Held on May 21, 2018, Between NRC and Entergy Regarding the Need for Additional Information to Support the River Bend Station License Renewal Application
RBG-47861, Response to License Renewal Application NRC Request for Additional Information Sets 14,15 and Operating Experience Review Clarification2018-05-29029 May 2018
Response to License Renewal Application NRC Request for Additional Information Sets 14,15 and Operating Experience Review Clarification
ML18149A2882018-05-24024 May 2018
NRR E-mail Capture - River Bend Station Request for Additional Information - Reactor Core Isolation Cooling Piping Modification (L-2018-LLA-0029)
ML18141A4882018-05-21021 May 2018
Draft Response (RAI 3.6.2.2.2.2-1a) from LRA Review Revised After the May 17, 2018 Call
ML18141A3172018-05-21021 May 2018
OE Draft RAI 3-0-5 Rogers
ML18131A2412018-05-11011 May 2018
RBS 012 Item 158a Response (RAI 3.2.2.3.2-1a) Revised - Received on 05/10/2018
ML18124A0092018-05-0303 May 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 15
ML18122A2312018-05-0202 May 2018
Draft Response to NRC Request for Additional Information (RAI) B.1.40-5 Service Water Integrity Generated from Staffs Review on the River Bend Station, Unit 1 License Renewal Application
ML18122A1262018-05-0202 May 2018
RAI B.1.17-1 Revised - w- header-footer-watermark
ML18121A3022018-05-0101 May 2018
Draft Response to NRC Request for Additional Information (RAI) 4.6-2a Generated from Staff'S Review on the River Bend License Renewal Application
ML18121A0292018-04-30030 April 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 14
ML18115A1632018-04-25025 April 2018
Draft Response on RBS LRA RAI B.1.21-2 Flow Accelerated Corrosion
ML18113A3322018-04-23023 April 2018
035 RB Buried Pipe 3rd Round RAI - Allik Holston
ML18103A0152018-04-12012 April 2018
NRR E-mail Capture - Summary of Public Telephone Conference Call Held on March 27, 2018, Between the U.S. Nuclear Regulatory Commission and Entergy and Final Requests for Additional Information for the Safety Review of the River Bend Statio
ML18073A0912018-03-14014 March 2018
NRC and Energy Public Meeting on Fatigue Analysis Related to River Bend License Renewal
ML18068A1872018-03-0909 March 2018
Revision of Final Request for Additional Information (RAI 2.3.3.17-2) for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 11
RBG-47834, Response to License Renewal Application NRC Request for Additional Information (RAI) Set 92018-03-0808 March 2018
Response to License Renewal Application NRC Request for Additional Information (RAI) Set 9
ML18065A2132018-03-0606 March 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 12
ML18060A1532018-03-0101 March 2018
NRR E-mail Capture - River Bend Station: Request for Additional Information Concerning New Technical Specification for Control Building Air Conditioning (L-2017-LLA-0291)
ML18058A0572018-02-23023 February 2018
Enclosurequest for Additional Information (Letter to J. Giddens Request for Additional Information Regarding Entergy Operations, Inc.'S Decommissioning Funding Plan Update)
ML18043A3512018-02-12012 February 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 11
ML18043A0082018-02-0808 February 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 10
ML18038B4702018-02-0707 February 2018
NRR E-mail Capture - Fyi_River Bend Station RAIs Set 9
ML18022A9412018-01-22022 January 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 8
ML18011A0462018-01-10010 January 2018
Notification of Cyber Security Inspection (NRC Inspection Report 05000458/2018406) and Request for Information
IR 05000458/20184062018-01-10010 January 2018
River Bend Station - Notification of Cyber Security Inspection (NRC Inspection Report 05000458/2018406) and Request for Information
ML18009A9092018-01-0909 January 2018
Final Requests for Additional Information for the Safety Review of the River Bend Station License Renewal Application (CAC No. MF9757) - Set 7
2024-09-16
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DRAFT - UNCERTIFIED INFORMATION Question RAI B.1.21-2 (Flow-Accelerated Corrosion)
Background
For the detection of aging effects program element, Section 4.8 of RBS EP 15 00007 cites procedure EN-DC-315, Flow-Accelerated Corrosion [FAC] Program, as the basis for being consistent with the GALL Report AMP XI.M17. Procedure EN-DC-315 states that specific software programs (i.e., CHECWORKS and FAC Manager Web Edition) shall be used in determining the remaining component life. Based on discussions during the AMP Audit breakout session, both software programs are classified as Level C, which does not require verification/validation activities. GALL Report AMP XI.M17 states that the FAC program is described in NSAC-202L and that components are suitable for continued service if the predicted wall thickness at the next scheduled inspection is greater than or equal to the minimum allowable wall thickness. NSAC-202L, Section 2, Elements of an Effective FAC Program, provides recommendations for ensuring that appropriate quality assurance is applied, including properly documenting work. Entergy report EC-0000072133, RF-19 Post-Outage Report, includes a signed output sheet from FAC Manager, which contains wall thickness data and the measured wear rate from each inspection.
Issue For safety-related components, it is not clear to the staff that the remaining component life is being properly determined because the wear rate values are taken from Level C software (i.e., CHECWORKS and FAC Manager Web Edition), which does not require validation and verification activities. Although the FAC Manager output sheets are signed as prepared and verified, the determination of the wear rate values cannot be independently verified based on the information provided.
Request Provide additional information to show that appropriate quality assurance has been applied to the calculated wear rates used in the determination of the schedule for inspection of safety-related components.
Response
Note: A previous response to RAI B.1.21-2 was submitted in letter RBG-47834, dated March 8, 2018.
The following response is the same as the response in letter RBG-47834 except additional information regarding software validation has been provided in the 3rd paragraph below. The following response supersedes the previous response submitted in letter RBG-47834.
CHECWORKS and FAC Manager Web Edition (FMWE) are Level C software which is used for day-to-day support activities and whose loss or failure would not affect the immediate ability to operate the plant but could threaten the plants long-term ability to operate. The Level C classification is appropriate because the software is not embedded in or integral to a safety-related (SR) structure, system or component (SSC), is not utilized in the design process of SR SSCs, is not embedded in or an integral part of a non-safety related (NSR) SSC used to support or maintain an important to safety SSC (e.g. surveillance, calibration, post-maintenance test),
is not used to determine Technical Specification, NRC regulation/commitments or 10CFR50 compliance, and is DRAFT - UNCERTIFIED INFORMATION Page 1 of 3
DRAFT - UNCERTIFIED INFORMATION not used to calibrate or maintain maintenance and test equipment (M&TE) used on safety-related or Technical Specification SSCs.
Level C software does not require verification, which consists of evaluating and analyzing products of each life cycle phase (e.g., requirements specification, design descriptions, code, and databases) through testing and reviews or audits to discover and correct deficiencies as early as possible. However, the CHECWORKS code was developed in accordance with the quality assurance policies of EPRI, which require a formal software plan and detailed program documentation. These policies also mandate that a list of program bugs be maintained. The FMWE code was developed in accordance with the quality assurance policies of Altran, which also require a formal testing plan, detailed program documentation, and a list of program bugs.
Level C software does require validation, which is the final testing activity and ensures that the software installation and integration into the production environment is successful. The installation is performed in accordance with a documented plan or vendor instructions which may include sample program inputs and outputs for use in verifying installation. In accordance with the Entergy software quality assurance procedure, each time CHECWORKS or FMWE is revised, FAC personnel validate the revised software using test cases and test databases before the software is placed in production mode. The validation tests provide the appropriate quality assurance to ensure that component wear, wear rate, predicted thickness, and remaining service life are calculated consistently with NSAC-202L.
Predictive model CHECWORKS is just one of the tools used to determine inspection eligibility and priority.
Selection of inspection locations for an outage is based on the following factors.
- previous inspection results
- CHECWORKS susceptibility ranking
- industry and plant-specific operating experience
- components selected to calibrate CHECWORKS
- components subject to off normal flow conditions, such as caused by a leaking valve
- susceptible non-modeled small bore piping that has not been inspected Measurement of actual wall thickness during inspections is the primary tool used in the FAC Program to determine component wear. The measured wall thickness is used to determine wear rates, predicted thickness, and remaining service life in FAC Manager Web Edition (FMWE) according to the following steps.
- Initial thickness of a component is determined by ultrasonic inspection prior to the component being placed in service or in the first ultrasonic inspection during its service life. If an examination has not previously been performed on the component, the initial thickness is determined by reviewing the initial ultrasonic data for that component. The area of maximum wall thickness within the same region as the worn area is identified. If the thickness is greater than the nominal component wall thickness, the maximum wall thickness within the relevant area is used as the initial thickness. If that thickness is less than the nominal wall thickness, the nominal wall thickness is used as the initial thickness.
- The projected wear rate is calculated by dividing the wear by the time between measurements or the time between when the component was placed in service and the time of the measurement. Wear is the amount of material removed or lost from a components wall thickness since baseline or subsequent to being placed in service and time is the actual plant operating hours, although calendar hours may be used for conservatism.
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- The remaining service life (RSL) is determined by subtracting the minimum acceptable wall thickness from the actual measured wall thickness, then dividing by the wear rate times a safety factor of 1.1.
- If the RSL of a component is greater than or equal to the number of hours in the next operating cycle, the component may be returned to service. If the component's RSL is greater than the number of hours in the next operating cycle but is less than the number of hours in the next two operating cycles, the component should be considered for re-inspection, repair or replacement during the next scheduled outage. If the component is acceptable for continued service, it shall be re-examined before, or during the cycle during which it is projected to wear to the minimum acceptable wall thickness.
Evaluation of wear rates, predicted thickness, and remaining service life is documented and reviewed by qualified FAC personnel or designated personnel qualified in accordance with the engineering calculation process. Therefore, appropriate quality assurance is applied to the calculated wear rates used in the determination of the schedule for inspection of safety-related components.
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