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| | number = ML14234A451 | | | number = ML14234A451 |
| | issue date = 09/04/2014 | | | issue date = 09/04/2014 |
| | title = Callaway Plant, Unit 1 - Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval (TAC MF3650) | | | title = Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval |
| | author name = Oesterle E R | | | author name = Oesterle E |
| | author affiliation = NRC/NRR/DORL/LPLIV-1 | | | author affiliation = NRC/NRR/DORL/LPLIV-1 |
| | addressee name = Diya F | | | addressee name = Diya F |
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Line 9: |
| | docket = 05000483 | | | docket = 05000483 |
| | license number = NPF-030 | | | license number = NPF-030 |
| | contact person = Lyon C F | | | contact person = Lyon C |
| | case reference number = TAC MF3650 | | | case reference number = TAC MF3650 |
| | document type = Code Relief or Alternative, Letter, Safety Evaluation | | | document type = Code Relief or Alternative, Letter, Safety Evaluation |
| | page count = 8 | | | page count = 8 |
| | project = TAC:MF3650, TAC:MF3650 | | | project = TAC:MF3650 |
| | stage = | | | stage = Other |
| }} | | }} |
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| =Text= | | =Text= |
| {{#Wiki_filter:Mr. Fadi Diya Senior Vice President and Chief Nuclear Officer Union Electric Company P.O. Box 620 Fulton, MO 65251 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 4, 2014 SUBJECT: CALLAWAY PLANT, UNIT 1-RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER (TAC NO. MF3650) Dear Mr. Diya: By letter dated March 19, 2014, Union Electric Company (dba Ameren Missouri, the licensee) submitted request for relief 13R-16, proposing an alternative to certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1. The scope of the request was limited to the temporary repair of leakage in the train "A" Component Cooling Water Heat Exchanger (EEG01A). In lieu of the IWA-4000 repair requirements, the licensee proposed an alternative applying provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A. The licensee requested authorization to use the proposed alternative pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR), Part 50, paragraph 55a(a)(3)(ii), on the basis that complying with the specified requirement would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the subject request and concludes, as set forth in the enclosed safety evaluation, that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(ii). Therefore, the staff authorizes use of the proposed alternative at Callaway Plant, Unit 1, until the end of the next refueling outage (i.e., Fuel Cycle 20), which is scheduled for October 2014. All other ASME Code, Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. The NRC staff provided verbal authorization for relief request 13R-16 during a teleconference with your staff on March 25, 2014. | | {{#Wiki_filter:UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 4, 2014 Mr. Fadi Diya Senior Vice President and Chief Nuclear Officer Union Electric Company P.O. Box 620 Fulton, MO 65251 |
| F. Diya -2-If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov. Docket No. 50-483 Enclosure: Safety Evaluation cc w/encl: Distribution via Listserv Sincerely, Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER 1.0 INTRODUCTION UNION ELECTRIC COMPANY CALLAWAY PLANT. UNIT 1 DOCKET NO. 50-483 By letter dated March 19, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 14079A529), Union Electric Company (dba Ameren Missouri, the licensee) requested relief from certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1 (Callaway). The scope of the request is limited to the temporary repair of leakage in the train "A" component cooling water (CCW) heat exchanger (EEG01A). In lieu of the IWA-4000 requirements, the alternative will apply provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A. Although the licensee has already implemented the temporary non-Code repair to control leakage from the subject component prior to the issuance of this safety evaluation (SE), this SE is being issued to document the decision made by the U.S. Nuclear Regulatory Commission (NRC) staff to grant the licensee's request by verbal authorization on March 25, 2014 (ADAMS Accession No. ML 14087A210). 2.0 REGULATORY EVALUATION Pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR) 50.55a(a)(3), alternatives to requirements may be authorized by the NRC if the licensee demonstrates that: (i) the proposed alternatives provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The licensee submitted the subject relief request, pursuant to 10 CFR 50.55a(a)(3)(ii). Enclosure | | |
| -2-3.0 LICENSEE EVALUATION 3.1 Component Affected Train "A" Component Cooling Water Heat Exchanger (EEG01A) tube side manway access, an ASME Class 3 Component. 3.2 ASME Code Requirements for which Relief is Requested The inservice inspection (lSI) Code of record for Callaway Plant for the third ten-year lSI interval is the ASME Code, Section XI 1998 Edition, including 2000 Addenda. Section C.12 of Chapter 0326 of the NRC Inspection Manual states, in part, that there is no generically approved alternative (non-Code repair) for temporary repair of flaws in a Class 3 vessel (such as EEG01A). The component must be repaired in accordance with the Code, or Code relief must be requested and approved from the NRC in order to apply a non-Code repair. ASME Code, Section XI requires that repair/replacement activities on ASME Code Class components be performed in accordance with the rules found in Article IWA-4000, "Repair/Replacement Activities." IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," allows mechanical clamping devices to be used as piping pressure boundary provided the requirements of Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundary," are met. Relief is requested to use IWA-4133 and to apply the provisions of ASME Code, Section XI, Mandatory Appendix IX for a temporary repair to the subject component, heat exchanger EEG01A. 3.3 Duration of Relief Request This relief request for Callaway is applicable to the end of the current fuel cycle, which is scheduled for October 2014. 3.4 Reason for Request On October 14, 2013, the licensee discovered a leak of essential service water (ESW) from the train "A" CCW heat exchanger EEG01A. The leak is due to a flaw from localized pitting and has been analyzed with ultrasonic examination. The bounding size of the flaw has been conservatively estimated to be a pit of a %-inch diameter. Given the conservative flaw size, the maximum calculated leak rate is 59.4 gallons per minute (gpm). An evaluation (Attachment A to the submittal) of the structural integrity of the subject component with a % inch diameter flaw was done according to ASME Code Case N-705, "Evaluation Criteria for Temporary Acceptance of Degradation in Moderate Energy Class 2 or 3 Vessels and Tanks" (accepted by the NRC and incorporated into Revision 16 of Regulatory Guide 1.147, "lnservice Inspection Code Case Acceptability, ASME Section XI, Division 1 "). The evaluation has determined that the flaw responsible for the leakage is acceptable and that structural integrity of EEG01A will be maintained through the current fuel cycle without repair.
| | ==SUBJECT:== |
| -3-If the flaw were to grow larger than diameter, the maximum calculated leak rate would be > 59.4 gallons per minute (gpm), which would reduce the inventory of the ultimate heat sink (UHS) over the 30-day ESW mission time. Compensatory actions have been taken by the licensee to assure the minimum UHS level is maintained above 75.5 percent full in order to provide sufficient inventory to compensate for existing ESW leakage plus the postulated 59.4 gpm loss and keep the UHS and ESW system operable. In an effort to provide additional margin to assure the minimum UHS level, a temporary mechanical clamping device is proposed, which would reduce leakage and would be able to be credited as a pressure boundary in the area of the flaw. 3.5 Licensee's Proposed Alternative to ASME Code IWA-4000 In its letter dated March 19, 2014, the licensee stated, in part, that: A mechanical clamp will be installed over the leakage location and will act as a credited pressure boundary in the vicinity of the pinhole leak.... A detailed description of the mechanical clamping device and the supporting calculations are supplied in Attachment B [to the submittal]. Until a permanent repair is performed in accordance with IWA-4000 to restore [heat exchanger] EEG01A to its design condition, the following actions are also being performed to satisfy the ASME Code Case N-705 requirements for monitoring and examination of the flaw.
| | CALLAWAY PLANT, UNIT 1- RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER (TAC NO. MF3650) |
| * Daily leakage monitoring is performed to assure the leakage remains within acceptable limits established in the Code Case N-705 evaluation. At present, there is no active leakage of ESW through the flaw. Following installation of the mechanical clamping device, this daily monitoring will also provide assurance that integrity of the credited pressure boundary is maintained. | | |
| * Ultrasonic examinations are performed quarterly to verify whether the degradation, including growth, continues to meet the acceptable limits established in the Code Case N-705 evaluation. The mechanical clamp pressure block has been designed to allow removal during these periodic examinations to facilitate measurement of the flaw. 3.6 Licensee's Basis for the Proposed Alternative An ASME Code Repair/Replacement of the heat exchanger would require draining of ESW from the CCW heat exchanger, making one ESW train inoperable, and would also make one emergency diesel generator inoperable. This activity would therefore place the plant in Action statements for Technical Specifications 3.7.7, "Component Cooling Water System," 3.7.8, "Essential Service Water System," and 3.8.1, "AC Sources-Operating," each of which requires restoration of the inoperable train within 72 hours. The Code Repair/Replacement activity on the CCW heat exchanger could last longer than 72 hours and would therefore necessitate a unit shutdown. Cycling the plant to perform an ASME Code repair of heat exchanger EEG01A would create a hardship based on the potential risks associated with unit cycling and any | | ==Dear Mr. Diya:== |
| -4-emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety. 4.0 NRC STAFF EVALUATION The NRC staff reviewed the submittal as a priority due to the operational issues for the unit. The licensee provided a detailed assessment of the structural integrity of the component according to ASME Code Case N-705 with the temporary repair and without the repair (leaving the assumed %-inch diameter flaw in place). In both cases, the assessment demonstrated that the CCW heat exchanger (EEG01A) can continue to operate until the next refueling outage in October of 2014. Given the postulated gallons per minute ESW leak, a margin still exists between the worst-case condition and the requirements for ESW system operability. During the coming summer months, the temperature of the ESW system will increase and without a repair, the margin for operability is reduced. In an effort to increase the margin of operability, the proposed alternative would install a temporary mechanical clamping device, which would eliminate the assumed leakage and would be able to be credited as a pressure boundary in the area of the leak. The design of the clamping device follows the requirements of IWA-4133. The licensee has used conservative assumptions regarding the flaw size, stress state, and potential for flaw growth until the next refueling outage, and determined that the postulated flaw would meet the structural margins required by the ASME Code Case N-705 under all normal, upset, emergency, and faulted conditions. Furthermore, the licensee has committed to daily visual inspection for leakage and additional quarterly ultrasonic inspections to demonstrate that the alternative still meets the Code Case N-705 requirements for monitoring and examination of the flaw (pit) that caused the leakage. The NRC staff has completed its review of the information provided by the licensee and the requirements for use of ASME Code Case N-705. The staff concludes that requiring the licensee to make a permanent Code-required repair to the leaking heat exchanger EEG01A before the next refueling outage would create a hardship based on the potential risks associated with unit cycling and any emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety. 5.0 CONCLUSION Based on the discussion above, the NRC staff concludes that the alternative proposed in the Relief Request 13R-16, to perform a non-Code repair to the leak found in the train "A" CCW heat exchanger EEG01A is acceptable because compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Therefore, pursuant to 10 CFR 50.55a{a){3)(ii), the staff authorizes the proposed Relief Request 13R-16 for Callaway Plant until the end of Fuel Cycle 20, which is scheduled for October 2014.
| | |
| -5-All other ASME Code, Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. Principal Contributor: P. Purtscher, NRR/DE/EVIB Date: September 4, 2014 F. Diya -2-If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov. Docket No. 50-483 Enclosure: Safety Evaluation cc w/encl: Distribution via Listserv DISTRIBUTION: PUBLIC LPL4-1 Reading RidsAcrsAcnw_MaiiCTR Resource RidsNrrPMCallaway Resource RidsNrrLAJBurkhardt Resource RidsRgn4MaiiCenter Resource RidsNrrDeEvib Resource RidsNrrDorllpl4-1 Resource PPurtscher, NRRIDE/EVIB ADAMS A ccess1on N o.: ML 14234A451 Sincerely, IRA/ Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation memo ae ugus '
| | By letter dated March 19, 2014, Union Electric Company (dba Ameren Missouri, the licensee) submitted request for relief 13R-16, proposing an alternative to certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1. The scope of the request was limited to the temporary repair of leakage in the train "A" Component Cooling Water Heat Exchanger (EEG01A). In lieu of the IWA-4000 repair requirements, the licensee proposed an alternative applying provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A. |
| * dtdA t 21 2014 OFFICE NRRIDORLILPL4-1/PM NRRIDORL/LPL4-1 /LA NRRIDE/EVIB/BC* NRR/DORL/LPL4-1 /BC(A) NAME Flyon JBurkhardt SRosenberg EOesterle DATE 9/3/14 9/3/14 8/21/14 9/4/14 OFFICIAL RECORD COPY
| | The licensee requested authorization to use the proposed alternative pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR), Part 50, paragraph 55a(a)(3)(ii), on the basis that complying with the specified requirement would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. |
| }} | | The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the subject request and concludes, as set forth in the enclosed safety evaluation, that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(ii). Therefore, the staff authorizes use of the proposed alternative at Callaway Plant, Unit 1, until the end of the next refueling outage (i.e., Fuel Cycle 20), which is scheduled for October 2014. |
| | All other ASME Code, Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. |
| | The NRC staff provided verbal authorization for relief request 13R-16 during a teleconference with your staff on March 25, 2014. |
| | |
| | F. Diya If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov. |
| | Sincerely, Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-483 |
| | |
| | ==Enclosure:== |
| | |
| | Safety Evaluation cc w/encl: Distribution via Listserv |
| | |
| | UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER UNION ELECTRIC COMPANY CALLAWAY PLANT. UNIT 1 DOCKET NO. 50-483 |
| | |
| | ==1.0 INTRODUCTION== |
| | |
| | By letter dated March 19, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14079A529), Union Electric Company (dba Ameren Missouri, the licensee) requested relief from certain American Society of Mechanical Engineers (ASME) |
| | Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1 (Callaway). The scope of the request is limited to the temporary repair of leakage in the train "A" component cooling water (CCW) heat exchanger (EEG01A). In lieu of the IWA-4000 requirements, the alternative will apply provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A. |
| | Although the licensee has already implemented the temporary non-Code repair to control leakage from the subject component prior to the issuance of this safety evaluation (SE), this SE is being issued to document the decision made by the U.S. Nuclear Regulatory Commission (NRC) staff to grant the licensee's request by verbal authorization on March 25, 2014 (ADAMS Accession No. ML14087A210). |
| | |
| | ==2.0 REGULATORY EVALUATION== |
| | |
| | Pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR) 50.55a(a)(3), alternatives to requirements may be authorized by the NRC if the licensee demonstrates that: (i) the proposed alternatives provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The licensee submitted the subject relief request, pursuant to 10 CFR 50.55a(a)(3)(ii). |
| | Enclosure |
| | |
| | 3.0 LICENSEE EVALUATION 3.1 Component Affected Train "A" Component Cooling Water Heat Exchanger (EEG01A) tube side manway access, an ASME Class 3 Component. |
| | 3.2 ASME Code Requirements for which Relief is Requested The inservice inspection (lSI) Code of record for Callaway Plant for the third ten-year lSI interval is the ASME Code, Section XI 1998 Edition, including 2000 Addenda. |
| | Section C.12 of Chapter 0326 of the NRC Inspection Manual states, in part, that there is no generically approved alternative (non-Code repair) for temporary repair of flaws in a Class 3 vessel (such as EEG01A). The component must be repaired in accordance with the Code, or Code relief must be requested and approved from the NRC in order to apply a non-Code repair. |
| | ASME Code, Section XI requires that repair/replacement activities on ASME Code Class components be performed in accordance with the rules found in Article IWA-4000, "Repair/Replacement Activities." IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," allows mechanical clamping devices to be used as piping pressure boundary provided the requirements of Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundary," are met. Relief is requested to use IWA-4133 and to apply the provisions of ASME Code, Section XI, Mandatory Appendix IX for a temporary repair to the subject component, heat exchanger EEG01A. |
| | 3.3 Duration of Relief Request This relief request for Callaway is applicable to the end of the current fuel cycle, which is scheduled for October 2014. |
| | 3.4 Reason for Request On October 14, 2013, the licensee discovered a leak of essential service water (ESW) from the train "A" CCW heat exchanger EEG01A. The leak is due to a flaw from localized pitting and has been analyzed with ultrasonic examination. The bounding size of the flaw has been conservatively estimated to be a pit of a %-inch diameter. |
| | Given the conservative flaw size, the maximum calculated leak rate is 59.4 gallons per minute (gpm). An evaluation (Attachment A to the submittal) of the structural integrity of the subject component with a % inch diameter flaw was done according to ASME Code Case N-705, "Evaluation Criteria for Temporary Acceptance of Degradation in Moderate Energy Class 2 or 3 Vessels and Tanks" (accepted by the NRC and incorporated into Revision 16 of Regulatory Guide 1.147, "lnservice Inspection Code Case Acceptability, ASME Section XI, Division 1"). |
| | The evaluation has determined that the flaw responsible for the leakage is acceptable and that structural integrity of EEG01A will be maintained through the current fuel cycle without repair. |
| | |
| | If the flaw were to grow larger than ~-inch diameter, the maximum calculated leak rate would be |
| | > 59.4 gallons per minute (gpm), which would reduce the inventory of the ultimate heat sink (UHS) over the 30-day ESW mission time. Compensatory actions have been taken by the licensee to assure the minimum UHS level is maintained above 75.5 percent full in order to provide sufficient inventory to compensate for existing ESW leakage plus the postulated 59.4 gpm loss and keep the UHS and ESW system operable. In an effort to provide additional margin to assure the minimum UHS level, a temporary mechanical clamping device is proposed, which would reduce leakage and would be able to be credited as a pressure boundary in the area of the flaw. |
| | 3.5 Licensee's Proposed Alternative to ASME Code IWA-4000 In its letter dated March 19, 2014, the licensee stated, in part, that: |
| | A mechanical clamp will be installed over the leakage location and will act as a credited pressure boundary in the vicinity of the pinhole leak.... A detailed description of the mechanical clamping device and the supporting calculations are supplied in Attachment B [to the submittal]. |
| | Until a permanent repair is performed in accordance with IWA-4000 to restore |
| | [heat exchanger] EEG01A to its design condition, the following actions are also being performed to satisfy the ASME Code Case N-705 requirements for monitoring and examination of the flaw. |
| | * Daily leakage monitoring is performed to assure the leakage remains within acceptable limits established in the Code Case N-705 evaluation. |
| | At present, there is no active leakage of ESW through the flaw. Following installation of the mechanical clamping device, this daily monitoring will also provide assurance that integrity of the credited pressure boundary is maintained. |
| | * Ultrasonic examinations are performed quarterly to verify whether the degradation, including growth, continues to meet the acceptable limits established in the Code Case N-705 evaluation. The mechanical clamp pressure block has been designed to allow removal during these periodic examinations to facilitate measurement of the flaw. |
| | 3.6 Licensee's Basis for the Proposed Alternative An ASME Code Repair/Replacement of the heat exchanger would require draining of ESW from the CCW heat exchanger, making one ESW train inoperable, and would also make one emergency diesel generator inoperable. This activity would therefore place the plant in Action statements for Technical Specifications 3.7.7, "Component Cooling Water System," 3.7.8, "Essential Service Water System," and 3.8.1, "AC Sources- Operating," each of which requires restoration of the inoperable train within 72 hours. The Code Repair/Replacement activity on the CCW heat exchanger could last longer than 72 hours and would therefore necessitate a unit shutdown. Cycling the plant to perform an ASME Code repair of heat exchanger EEG01A would create a hardship based on the potential risks associated with unit cycling and any |
| | |
| | emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety. |
| | 4.0 NRC STAFF EVALUATION The NRC staff reviewed the submittal as a priority due to the operational issues for the unit. |
| | The licensee provided a detailed assessment of the structural integrity of the component according to ASME Code Case N-705 with the temporary repair and without the repair (leaving the assumed %-inch diameter flaw in place). In both cases, the assessment demonstrated that the CCW heat exchanger (EEG01A) can continue to operate until the next refueling outage in October of 2014. Given the postulated gallons per minute ESW leak, a margin still exists between the worst-case condition and the requirements for ESW system operability. |
| | During the coming summer months, the temperature of the ESW system will increase and without a repair, the margin for operability is reduced. In an effort to increase the margin of operability, the proposed alternative would install a temporary mechanical clamping device, which would eliminate the assumed leakage and would be able to be credited as a pressure boundary in the area of the leak. The design of the clamping device follows the requirements of IWA-4133. The licensee has used conservative assumptions regarding the flaw size, stress state, and potential for flaw growth until the next refueling outage, and determined that the postulated flaw would meet the structural margins required by the ASME Code Case N-705 under all normal, upset, emergency, and faulted conditions. Furthermore, the licensee has committed to daily visual inspection for leakage and additional quarterly ultrasonic inspections to demonstrate that the alternative still meets the Code Case N-705 requirements for monitoring and examination of the flaw (pit) that caused the leakage. |
| | The NRC staff has completed its review of the information provided by the licensee and the requirements for use of ASME Code Case N-705. The staff concludes that requiring the licensee to make a permanent Code-required repair to the leaking heat exchanger EEG01A before the next refueling outage would create a hardship based on the potential risks associated with unit cycling and any emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety. |
| | |
| | ==5.0 CONCLUSION== |
| | |
| | Based on the discussion above, the NRC staff concludes that the alternative proposed in the Relief Request 13R-16, to perform a non-Code repair to the leak found in the train "A" CCW heat exchanger EEG01A is acceptable because compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Therefore, pursuant to 10 CFR 50.55a{a){3)(ii), the staff authorizes the proposed Relief Request 13R-16 for Callaway Plant until the end of Fuel Cycle 20, which is scheduled for October 2014. |
| | |
| | All other ASME Code, Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. |
| | Principal Contributor: P. Purtscher, NRR/DE/EVIB Date: September 4, 2014 |
| | |
| | F. Diya If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov. |
| | Sincerely, IRA/ |
| | Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-483 |
| | |
| | ==Enclosure:== |
| | |
| | Safety Evaluation cc w/encl: Distribution via Listserv DISTRIBUTION: |
| | PUBLIC LPL4-1 Reading RidsAcrsAcnw_MaiiCTR Resource RidsNrrPMCallaway Resource RidsNrrLAJBurkhardt Resource RidsRgn4MaiiCenter Resource RidsNrrDeEvib Resource RidsNrrDorllpl4-1 Resource PPurtscher, NRRIDE/EVIB ADAMS Access1on No.: ML14234A451 |
| | * memo dtdA ae ugus t 21 2014 OFFICE NRRIDORLILPL4-1/PM NRRIDORL/LPL4-1 /LA NRRIDE/EVIB/BC* NRR/DORL/LPL4-1 /BC(A) |
| | NAME Flyon JBurkhardt SRosenberg EOesterle DATE 9/3/14 9/3/14 8/21/14 9/4/14 OFFICIAL RECORD COPY}} |
Letter Sequence Other |
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MONTHYEARML14084A1362014-03-25025 March 2014
NRR E-mail Capture - Callaway I3R-16 Phoncon
Project stage: Other
ML14084A6192014-03-25025 March 2014
NRR E-mail Capture - Callaway - Verbal Relief I3R-16
Project stage: Other
ML14087A2102014-04-0808 April 2014
Summary of 3/25/14 Verbal Relief Telephone Conference, Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval
Project stage: Other
ML14234A4512014-09-0404 September 2014
Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval
Project stage: Other
2014-04-08
[Table View] |
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Category:Code Relief or Alternative
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Authorization and Safety Evaluation for Alternative Request C3R-01
ML24052A3662024-02-26026 February 2024
Regulatory Audit Plan in Support of Proposed Alternative to ASME Code, Section XI Requirements for Containment Building Inspections
ML20225A2922020-08-12012 August 2020
Request to Use a Portion of a Later Edition of the ASME B&PV Code, Section XI
ML19079A1482019-04-0101 April 2019
Request for Alternative I4R-05 to Reactor Vessel Nozzle Weld Examination Frequency Requirements (EPID L-2018-LLR-0051
ML18313A0692018-11-26026 November 2018
Request for Relief I4R-01 Related to the Inservice Inspection Program for Class 3 Buried High Density Polyethylene Piping
ULNRC-06420, Request 14R-05 for Relief from Requirements of ASME Code Case N-770-2 Regarding Inspection Intervals for Reactor Vessel Nozzle Dissimilar Metal Welds2018-04-0909 April 2018
Request 14R-05 for Relief from Requirements of ASME Code Case N-770-2 Regarding Inspection Intervals for Reactor Vessel Nozzle Dissimilar Metal Welds
ML17262A7002017-10-0303 October 2017
Request for Alternative I4R-04 Applicable to the Fourth 10-Year Inspection Program Interval
ML17254A1202017-09-25025 September 2017
Request for Alternative No. PR-07 from the Requirements of the ASME Code for the Fourth 10-Year Inservice Testing Interval
ML17058A4432017-03-0606 March 2017
Request for Alternative I4R-03 Applicable to the Fourth 10-Year Inservice Inspection Program Interval
ML16223A7122016-08-30030 August 2016
Relief Request No. 13R-08 from Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds, for Piping Welds, Third 10-Year Inservice Inspection Interval
ML16055A4642016-03-17017 March 2016
Relief Requests 13R-09 (Steam Generator Tubesheet Weld), 13R-11 (Pressurizer Welds) from Code Case N-460 and 13R-18 (SG Weld), from Appendix Viii Requirements, Third 10-Year Inservice Inspection Interval (CAC MF6735-MF6737)
ML16027A1582016-01-29029 January 2016
Relief Request I4R-02 from Requirements of ASME Code Section XI, Table IWF-2500-1 for 100% Visual Examination of Class 1 Supports, Fourth 10-Year Inservice Inspection Interval
ML15064A1252015-05-12012 May 2015
Request for Relief I4R-01 from ASME Code Requirements for Replacement of Class 3 Essential Service Water Buried Piping with High Density Polyethylene Piping, for the Fourth 10-year Inservice Testing Interval
ML15035A1482015-02-10010 February 2015
Relief Request 13R-17, Proposed Alternative to ASME Code, Section XI Requirements, Which Extends Reactor Vessel Inservice Inspection Frequency from 10 to 20 Years, Third 10-Year Interval
ML14239A0972014-09-0404 September 2014
Request for Relief I3R-15, ASME Code Class 1 Pressure-Retaining Piping/Components Leakage Testing at Full Pressure, Third 10-Year Inservice Inspection Interval
ML14234A4512014-09-0404 September 2014
Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval
ML14178A7692014-07-15015 July 2014
Requests for Relief PR-01, PR-02, PR-03, PR-04, and PR-06 (PR-05 Withdrawn), ASME OM Code Cases for Group a and B Pumps for Fourth 10-Year Inservice Testing Interval
ML14027A0572014-01-29029 January 2014
Relief Request PR-07, Testing Frequency for Pumps and Valves, Third 10-year Inservice Testing Interval
ML13246A3042013-08-30030 August 2013
Verbal Authorization Email, Relief Request PR-07, Testing Frequency for Pumps and Valves, Third 10-year Inservice Testing Interval
ML13126A3202013-05-0707 May 2013
Summary of Telephone Conference, Verbal Authorization of Relief Request I3R-14. Proposed Alternative to ASME Code Requirements for Leakage Testing of RPV Head Flange Leakoff Lines, Third 10-Year ISI Interval.
ML12258A0452012-09-18018 September 2012
Relief Request VR-01 from Requirements of ASME OM Code, Mandatory Appendix I, One-time Extension for 5-Year Replacement Interval, from 4/11/12 to 6/2013, Main Steam Isolation Valve Actuator Rupture Disks
ML1211502472012-05-0303 May 2012
Memo to File, Verbal Authorization, Relief Request VR-01 from Requirements of ASME OM Code Mandatory Appendix I, One-time Extension Replacement of Main Steam Isolation Valve Actuator Rupture Disks
ML1201907482012-02-16016 February 2012
Relief Request 13R-13, Alternative to ASME Code Section XI Requirements for Performance of Second Successive Exam of C Cold Leg Safe-End to Elbow Weld, Third 10-Year Inservice Inspection
ML0831002882008-11-0707 November 2008
Relief Request 13R-10 Approved on October 31, 2008, for Third 10-Year Inservice Inspection Interval for Use of Polyethylene Pipe in Lieu of Carbon Steel Pipe in Buried Essential Service Water Piping System
ML0818406062008-07-0303 July 2008
Approval of Second Extension Request for Corrective Actions GL 2004-02, Potential Impact of Debris Blockage on Emergency Recirculation During Design Basis Accidents at Pressurized Water Reactors.
ML0731114422007-12-10010 December 2007
Correction to Authorization of Relief Request ISI-39 for the Second 10-Year Inservice Inspection Interval
ML0729803972007-10-30030 October 2007
Relief Request ISI-38, Reactor Pressure Vessel Inlet Safe-End to-Elbow Welds Proposed Alternative Examination for Second 10-Year Inservice Inspection Interval
ML0724000922007-09-17017 September 2007
Issuance of Relief Requests (Rrs) ISI-36, ISI-37, and ISI-38 for Second Year Inservice Inspection (ISI) Interval
ML0725504882007-08-30030 August 2007
10 CFR 50.55a Request: Proposed Alternative to ASME Section Xi Requirements for Replacement of Class 3 Buried Piping
ML0715203292007-07-10010 July 2007
Request for Alternatives for Application of Structural Weld Overlays to Pressurizer Dissimilar Metal Nozzle Welds for Third 10-Year Inservice Inspection Program Interval
ML0705803332007-03-15015 March 2007
Authorization of Relief Request No. ISI-33 for Second 10-Year and Third 10-Year ISI Interval
ML0635203182007-01-18018 January 2007
Request for Relief No. ISI-35 for Second 10-year Inservice Inspection Interval
ML0700303362007-01-18018 January 2007
Relief Request ISI-41 for the Second 10-year Inservice Inspection Interval
ML0630604782006-12-0707 December 2006
Relief Request 13R-04 for the Third 10-Year Interval Inservice Inspection
ML0629302822006-11-17017 November 2006
Relief Requests I3R-05 and I3R-06 for the Third Inservice Inspection Interval
ULNRC-05183, Requests for Relief from ASME Section XI Code Inservice Examination Requirements2006-10-25025 October 2006
Requests for Relief from ASME Section XI Code Inservice Examination Requirements
ML0614301312006-06-15015 June 2006
Relief, Third 10-Year Interval Inservice Inspection Program Relief Request I3R-02
ML0520802152005-08-18018 August 2005
Relief, Use a Subsequent Edition of ASME Code Examinations for the Third Inservice Inspection Interval
ML0515302072005-06-22022 June 2005
6/22/05 Callaway, Unit 1 - Relief Requests ISI-24,ISI-25 and ISI-26 of the Second 10-Year Inservice Inspection (ISI) Interval (Tacs. MC4435 and MC4436)
ML0507601292005-05-19019 May 2005
Relief, Request for Relief from Certain ASME Code Examinations for the Second Inservice Inspection Interval
ULNRC-05092, Revision to Approve Request for Relief from ASME Section III Requirements Regarding Non-destructive Examination of Welds Performed Under Site Repair/Replacement Program2004-11-18018 November 2004
Revision to Approve Request for Relief from ASME Section III Requirements Regarding Non-destructive Examination of Welds Performed Under Site Repair/Replacement Program
ULNRC-05049, Union Electric Company Callaway Plant Request for Relief from ASME Section XI Code Inservice Examination Requirements2004-09-0303 September 2004
Union Electric Company Callaway Plant Request for Relief from ASME Section XI Code Inservice Examination Requirements
ML0414100712004-05-19019 May 2004
Relief, ASME Code Requirements on the Use of Weld Overlay Reinforcement to Restore Wall Thickness of ASME Class 2 Carbon Steel Main Feedwater Piping.
ML0414100352004-05-19019 May 2004
Relief, Second Ten-Year Interval Inservice Inspection Program Relief Request to Use an Alternative Examination Method
ULNRC-04993, Revision of Request for Relief from ASME Section XI Requirements in Order to Temporarily Restore Wall Thickness of ASME Class 2 Carbon Steel Main Feedwater Piping by Weld Overlay Reinforcement2004-05-0707 May 2004
Revision of Request for Relief from ASME Section XI Requirements in Order to Temporarily Restore Wall Thickness of ASME Class 2 Carbon Steel Main Feedwater Piping by Weld Overlay Reinforcement
ML0409806642004-04-0707 April 2004
4/7/04 Callaway Plant - Request for Relief from ASME Code Requirements on the Use of Weld Overlay Reinforcement to Restore Wall Thickness of ASME Class 2 Carbon Steel Main Feedwater Piping
ULNRC-04879, Requests for Relief Regarding Implementation of ASME Section XI Appendix VII Requirements2003-08-14014 August 2003
Requests for Relief Regarding Implementation of ASME Section XI Appendix VII Requirements
ML0318305352003-07-0101 July 2003
Second Ten-Year Interval Inservice Inspection Program Relief Request to Use an Alternative Examination Method (Tac. MB6534)
ML0134602652002-01-30030 January 2002
Relief, Application of Risk-Informed Inservice Inspection Program for the American Society of Mechanical Engineers Boilers and Pressure Vessel Code Class 1 and 2 TAC No MB1205)
2024-08-13
[Table view]
Category:Letter
MONTHYEARIR 05000483/20240032024-10-23023 October 2024
Integrated Inspection Report 05000483/2024003
IR 05000483/20240132024-10-21021 October 2024
Design Basis Assurance Inspection (Programs) Inspection Report 05000483/2024013
IR 05000483/20244012024-10-0909 October 2024
Material Control and Accounting Program Inspection Report 05000483/2024401 Public
ULNRC-06901, Concurrent Inoperability of Control Room Air Conditioning System Train and Opposite Train Emergency Diesel Generator Results in Condition Prohibited by Technical Specifications Limiting (Letter)2024-10-0101 October 2024
Concurrent Inoperability of Control Room Air Conditioning System Train and Opposite Train Emergency Diesel Generator Results in Condition Prohibited by Technical Specifications Limiting (Letter)
ML24247A3042024-09-11011 September 2024
Regulatory Audit Questions for License Renewal Commitments 34 and 35 (EPID L-2024-LRO-0009) - Non-Proprietary
IR 05000483/20244032024-08-28028 August 2024
Security Baseline Inspection 05000483-2024-403
IR 05000483/20240052024-08-14014 August 2024
Updated Inspection Plan for Callaway Plant (Report 05000483/2024005)
IR 05000483/20253012024-08-0505 August 2024
Notification of NRC Initial Operator Licensing Examination 05000483/2025301
ML24212A2822024-08-0202 August 2024
Regulatory Audit Summary Concerning Review of Request No. C3R-01 for Proposed Alternative to ASME Code, Section XI Requirements for Containment Building Inspections
IR 05000483/20240022024-07-18018 July 2024
And Independent Spent Fuel Storage Installation Integrated Inspection Report 05000483/2024002 and 07201045/2024001
ML24185A1032024-07-16016 July 2024
2024 Biennial Problem Identification and Resolution Inspection Report
ULNRC-06892, Independent Spent Fuel Storage Installation Registration of Dry Spent Fuel Storage Canister HGMPC00062024-06-26026 June 2024
Independent Spent Fuel Storage Installation Registration of Dry Spent Fuel Storage Canister HGMPC0006
ULNRC-06891, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00052024-06-26026 June 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0005
ULNRC-06884, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00022024-06-12012 June 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0002
ULNRC-06886, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00042024-06-12012 June 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0004
ULNRC-06885, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00032024-06-12012 June 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0003
ML24144A0492024-06-11011 June 2024
Requests for Relief from ASME OM Code Pump and Valve Testing Requirements for Fifth 120-Month Inservice Testing Interval
ML24158A5222024-06-0606 June 2024
Application to Revise Technical Specifications to Adopt Tstf-569, Rev. 2, Revise Response Time Testing Definition (LDCN 24-0008)
ML24178A1132024-06-0606 June 2024
Ameren Missouris Intent to Adopt Revision 1 to Amendment 0 of Certificate of Compliance No. 1040 as Applicable to the ISFSI at the Callaway Plant Site
ML24143A1632024-05-23023 May 2024
Independent Spent Fuel Storage Installation Registration of Dry Spent Storage Canister HGMPC0001
ULNRC-06882, Independent Spent Fuel Storage Installation Registration of Dry Spent Fuel Storage Canister HGMPC00122024-05-16016 May 2024
Independent Spent Fuel Storage Installation Registration of Dry Spent Fuel Storage Canister HGMPC0012
ML24137A2342024-05-16016 May 2024
Independent Spent Fuel Storage Installation - Registration of Dry Spent Fuel Storage Canister HGMPC0011
ML24122A1502024-05-0707 May 2024
Audit Plan to Support Review of Steam Generator License Renewal Response to Commitment Nos 34 and 35
ULNRC-06877, Final Safety Analysis Report Revision OL-27 and Technical Specification Bases Revision 252024-05-0606 May 2024
Final Safety Analysis Report Revision OL-27 and Technical Specification Bases Revision 25
IR 05000483/20244022024-05-0606 May 2024
Security Baseline Inspection Report 05000483/2024402 (Full Report)
IR 05000483/20240112024-05-0101 May 2024
NRC Post-Approval Site Inspection for License Renewal (Phase 2) Report 05000483/2024011
ULNRC-06856, CFR 50.59 and 10 CFR 72.48 Summary Report2024-05-0101 May 2024
CFR 50.59 and 10 CFR 72.48 Summary Report
ULNRC-06869, Submittal of Callaway, Unit 1, 2023 Annual Radiological Environmental Operating Report2024-04-30030 April 2024
Submittal of Callaway, Unit 1, 2023 Annual Radiological Environmental Operating Report
ML24122A1132024-04-30030 April 2024
Submittal of Callaway, Unit 1, 2023 Annual Radioactive Effluent Release Report
ULNRC-06876, Registration of Dry Spent Fuel Storage Canister HGMPC00102024-04-25025 April 2024
Registration of Dry Spent Fuel Storage Canister HGMPC0010
ML24108A1082024-04-17017 April 2024
Independent Spent Fuel Storage Installation Registration of Dry Spent Fuel Storage Canister HGMPC0009
ULNRC-06871, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00072024-04-17017 April 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0007
ULNRC-06872, Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC00082024-04-17017 April 2024
Independent Spent Fuel Storage Installation, Registration of Dry Spent Fuel Storage Canister HGMPC0008
ULNRC-06866, Submittal of Cycle 26 Commitment Change Summary Report2024-04-17017 April 2024
Submittal of Cycle 26 Commitment Change Summary Report
IR 05000483/20240012024-04-16016 April 2024
Integrated Inspection Report 05000483/2024001
IR 05000483/20244042024-04-0909 April 2024
Cyber Security Inspection Report 05000483/2024404
ML24088A3212024-04-0101 April 2024
Notification of Commercial Grade Dedication Inspection (05000483/2024013) and Request for Information
ML24086A5132024-03-26026 March 2024
CFR 50.46 Annual Report Regarding ECCS Evaluation Model Revisions
ULNRC-06863, Submittal of Annual Exposure Report for 20232024-03-20020 March 2024
Submittal of Annual Exposure Report for 2023
ML24079A1622024-03-19019 March 2024
Re Nuclear Property Insurance Reporting
ML24066A1932024-03-0707 March 2024
2024 Callaway Plant Notification of Biennial Problem Identification and Resolution Inspection and Request for Information
ULNRC-06852, Owners Activity Reports (OAR-1 Forms) for Cycle/Refuel 262024-03-0505 March 2024
Owners Activity Reports (OAR-1 Forms) for Cycle/Refuel 26
IR 05000483/20230062024-02-28028 February 2024
Annual Assessment Letter for Callaway Plant Report 05000483/2023006
ML24052A3662024-02-26026 February 2024
Regulatory Audit Plan in Support of Proposed Alternative to ASME Code, Section XI Requirements for Containment Building Inspections
ULNRC-06858, Completion of License Renewal Activities Prior to Entering the Period of Extended Operation2024-02-21021 February 2024
Completion of License Renewal Activities Prior to Entering the Period of Extended Operation
ML24036A1712024-02-20020 February 2024
Exemption from Select Requirements of 10 CFR Part 73 (EPID L-2023-LLE-0079 (Security Notifications, Reports, and Recordkeeping and Suspicious Activity Reporting))
ULNRC-06853, Submittal of 2023 Fitness for Duty Performance Data Per Per 10 CFR 26.7172024-01-29029 January 2024
Submittal of 2023 Fitness for Duty Performance Data Per Per 10 CFR 26.717
ML24008A0552024-01-19019 January 2024
Acceptance of Requested Licensing Action - Proposed Alternative to the Requirements of the ASME Code (EPID L-2023-LLR- 0061)
IR 05000483/20230042024-01-19019 January 2024
– Integrated Inspection Report 05000483/2023004
ML23353A1712024-01-18018 January 2024
Issuance of Amendment No. 237 to Clarify Support System Requirements for the Residual Heat Removal System and Control Room Air Conditioning System Under Technical Specifications 3.4.8, 3.7.11, and 3.9.6
2024-09-11
[Table view]
Category:Safety Evaluation
MONTHYEARML23353A1712024-01-18018 January 2024
Issuance of Amendment No. 237 to Clarify Support System Requirements for the Residual Heat Removal System and Control Room Air Conditioning System Under Technical Specifications 3.4.8, 3.7.11, and 3.9.6
ML23347A1212024-01-11011 January 2024
Issuance of Amendment No. 236 to Adopt TSTF-501, Revision 1, Relocate Stored Fuel Oil and Lube Volume Values to Licensee Control EPID L-2023-LLA-0046)
ML23234A1522023-10-0505 October 2023
Exemption from the Requirements of 10 CFR Part 50, Section 50.46, and Appendix K Regarding Use of M5 Cladding Material (EPID L-2022-LLE-0030) (Letter)
ML23240A3692023-10-0505 October 2023
Issuance of Amendment No. 235 to Revise Technical Specifications to Use of Framatome Gaia Fuel (EPID L-2022-LLA-0150) (Non-Proprietary)
ML23228A0252023-09-25025 September 2023
Issuance of Amendment No. 234 to Revise Technical Specification 5.5.16, Containment Leakage Rate Testing Program, for Permanent Extension of Type a and Type C Leak Rate Test Frequencies
ML23261C3852023-09-25025 September 2023
Safety Evaluation for Operating Quality Assurance Manual Revision 36A
ML23166B0882023-09-20020 September 2023
Issuance of Amendment No. 233 for Adoption of Alternative Source Term and Revision of Technical Specifications
ML22361A0702023-02-24024 February 2023
Issuance of Amendment No. 231 for Revision to Radiological Emergency Response Plan Regarding Response and Notification Goals
ML23019A1752023-01-30030 January 2023
Issuance of Amendment No. 230 to Revise Technical Specifications to Adopt TSTF-577, Revision 1, Revised Frequencies for Steam Generator Tube Inspections
ML22301A0072022-12-0202 December 2022
Issuance of Amendment No. 229 to Revise Technical Specifications to Adopt TSTF-505, Revision 2, and TSTF-439, Revision 2
ML22220A1302022-10-21021 October 2022
Exemptions from the Requirements of 10 CFR 50.46 and 10 CFR Part 50 Appendix a, General Design Criteria 35, 38, and 41 (EPID L-2021-LLE-0021) (Cover Letter)
ML22220A1322022-10-21021 October 2022
Issuance of Amendment No. 228 Re; Revise Technical Specifications to Address Generic Safety Isusue-191 and Respond to Generic Letter 2004-02 Using Risk-Informed Approach
ML22053A2832022-04-0707 April 2022
Issuance of Amendment No. 227 Revise Technical Specifications to Adopt Technical Specifications Task Force (TSTF) Traveler TSTF-529, Revision 4, Clarify Use and Application Rules
ML21344A0052021-12-29029 December 2021
Issuance of Amendment No. 226 Regarding Adoption of 10 CFR 50.69, Risk-Informed Categorization and Treatment of Structures, Systems and Components for Nuclear Power Plants
ML21053A1262021-03-24024 March 2021
Issuance of Amendment No. 225 to Revise Technical Specification Administrative Control 5.3.1 to Remove Details Specified for the Qualification of Certain Positions within the Unit Staff
ML20218A4102020-11-0303 November 2020
Issuance of Amendment No. 224 Performance Based Method Alternative for Thermal Insulation Material
ML20246G5702020-10-16016 October 2020
Issuance of Amendment No. 223 One-Time Deferral of the Steam Generator Tube Inspections
ML20230A3872020-08-31031 August 2020
Request to Use a Provision of a Later Edition of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI
ML20216A6812020-08-0606 August 2020
Operating Quality Assurance Manual Change Revision 34B (EPID L-2020-LLQ-0004 (COVID-19))
ML20141L7452020-06-0808 June 2020
Operating Quality Assurance Manual Change Revision 34A
ML20107H9782020-04-20020 April 2020
COVID-19 Relief Request CC-01 Containment Tendon Inspection
ML19283C4812019-12-0606 December 2019
Issuance of Amendment No. 221 Main Turbine Control Slave Relay Testing
ML19158A2902019-07-30030 July 2019
Issuance of Amendment No. 220 Regarding Emergency Action Level Scheme Changes
ML19073A0012019-04-18018 April 2019
Issuance of Amendment No. 219 to Add New Technical Specification 3.7.20, Class 1E Electrical Equipment Air Conditioning (A/C) System
ML19079A1482019-04-0101 April 2019
Request for Alternative I4R-05 to Reactor Vessel Nozzle Weld Examination Frequency Requirements (EPID L-2018-LLR-0051
ML18313A0692018-11-26026 November 2018
Request for Relief I4R-01 Related to the Inservice Inspection Program for Class 3 Buried High Density Polyethylene Piping
ML18124A0262018-05-30030 May 2018
Issuance of Amendment No. 218 FSAR Revision Compliance with Regulatory Guide 1.106 Regarding MOV Thermal Overload Protection
ML17262A7002017-10-0303 October 2017
Request for Alternative I4R-04 Applicable to the Fourth 10-Year Inspection Program Interval
ML17254A1202017-09-25025 September 2017
Request for Alternative No. PR-07 from the Requirements of the ASME Code for the Fourth 10-Year Inservice Testing Interval
ML17236A0822017-09-15015 September 2017
Issuance of Amendment No. 217 Replacement of Methodology in Technical Specification 5.6.5, Core Operating Limits Report (Colr),
ML17170A3202017-06-20020 June 2017
Safety Evaluation Input - for Ameren Missouri Request to Amend Callaway Plant, Unit 1, Technical Specification 5.6.5, Core Operating Limits Report -
ML17058A4432017-03-0606 March 2017
Request for Alternative I4R-03 Applicable to the Fourth 10-Year Inservice Inspection Program Interval
ML17010A3322017-02-0202 February 2017
Safety Evaluation Regarding Implementation of Mitigating Strategies and Reliable Spent Fuel Pool Instrumentation Related to Orders EA-12-049 and EA-12-051
ML16223A7122016-08-30030 August 2016
Relief Request No. 13R-08 from Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds, for Piping Welds, Third 10-Year Inservice Inspection Interval
ML16089A1672016-04-0101 April 2016
Review and Approval of Quality Assurance Plan Change Per Nuclear Energy Institute (NEI) 14-05A, Revision 1
ML16055A4642016-03-17017 March 2016
Relief Requests 13R-09 (Steam Generator Tubesheet Weld), 13R-11 (Pressurizer Welds) from Code Case N-460 and 13R-18 (SG Weld), from Appendix Viii Requirements, Third 10-Year Inservice Inspection Interval (CAC MF6735-MF6737)
ML16020A5162016-02-29029 February 2016
Issuance of Amendment No. 216, Revise Technical Specification (TS) 2.1.1.1 and TS 5.6.5, to Remove Uncertainties from Departure from Nucleate Boiling Ratio Safety Limit and Adopt WCAP-14565-P-A Methodology
ML15324A1142016-02-0202 February 2016
Issuance of Amendment No. 215, Adopt Technical Specification Task Force (TSTF) Traveler TSTF-510, Revision 2, Revision to Steam Generator Program Inspection Frequencies and Tube Sample Selection
ML16027A1582016-01-29029 January 2016
Relief Request I4R-02 from Requirements of ASME Code Section XI, Table IWF-2500-1 for 100% Visual Examination of Class 1 Supports, Fourth 10-Year Inservice Inspection Interval
ML15328A0592016-01-28028 January 2016
Issuance of Amendment No. 214, Request to Revise Operating License Condition Related to Cyber Security Plan Milestone 8 Full Implementation Date
ML15258A5102015-10-28028 October 2015
Issuance of Amendment No. 213, Adopt Technical Specification Task Force Traveler TSTF-523, Generic Letter 2008-01, Managing Gas Accumulation
ML15251A4932015-10-0707 October 2015
Issuance of Amendment No. 212, Request to Upgrade the Emergency Action Level Scheme by Adopting Nuclear Energy Institute NEI 99-01, Revision 6
ML15064A1252015-05-12012 May 2015
Request for Relief I4R-01 from ASME Code Requirements for Replacement of Class 3 Essential Service Water Buried Piping with High Density Polyethylene Piping, for the Fourth 10-year Inservice Testing Interval
ML15064A0282015-03-31031 March 2015
Issuance of Amendment No. 211, Request to Revise Final Safety Analysis Report Standard Plant Section 3.6 for High Density Polyethylene (Hdpe) Crack Exclusion
ML15035A1482015-02-10010 February 2015
Relief Request 13R-17, Proposed Alternative to ASME Code, Section XI Requirements, Which Extends Reactor Vessel Inservice Inspection Frequency from 10 to 20 Years, Third 10-Year Interval
ML14350B2392015-01-20020 January 2015
Issuance of Amendment No. 210, Revise Technical Specification LCO 3.4.12, Cold Overpressure Mitigation System (Coms), to Clarify No Limitation on Normal Charging Pump Use During Modes 4-6
ML14234A4512014-09-0404 September 2014
Relief Request I3R-16, Temporary Non-Code Repair of the Train a Component Cooling Water Heat Exchanger to Control ESW Leakage, Third 10-Year Inservice Inspection Interval
ML14178A7692014-07-15015 July 2014
Requests for Relief PR-01, PR-02, PR-03, PR-04, and PR-06 (PR-05 Withdrawn), ASME OM Code Cases for Group a and B Pumps for Fourth 10-Year Inservice Testing Interval
ML14175A3902014-07-0101 July 2014
Issuance of Amendment No. 209, Adoption of Technical Specification Task Force Change Traveler TSTF-522-A, Revision 0, Revise Ventilation System to Operate for 10 Hours Per Month, Using CLIIP
ML14027A0572014-01-29029 January 2014
Relief Request PR-07, Testing Frequency for Pumps and Valves, Third 10-year Inservice Testing Interval
2024-01-18
[Table view] |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 4, 2014 Mr. Fadi Diya Senior Vice President and Chief Nuclear Officer Union Electric Company P.O. Box 620 Fulton, MO 65251
SUBJECT:
CALLAWAY PLANT, UNIT 1- RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER (TAC NO. MF3650)
Dear Mr. Diya:
By letter dated March 19, 2014, Union Electric Company (dba Ameren Missouri, the licensee) submitted request for relief 13R-16, proposing an alternative to certain American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1. The scope of the request was limited to the temporary repair of leakage in the train "A" Component Cooling Water Heat Exchanger (EEG01A). In lieu of the IWA-4000 repair requirements, the licensee proposed an alternative applying provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A.
The licensee requested authorization to use the proposed alternative pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR), Part 50, paragraph 55a(a)(3)(ii), on the basis that complying with the specified requirement would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the subject request and concludes, as set forth in the enclosed safety evaluation, that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(ii). Therefore, the staff authorizes use of the proposed alternative at Callaway Plant, Unit 1, until the end of the next refueling outage (i.e., Fuel Cycle 20), which is scheduled for October 2014.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
The NRC staff provided verbal authorization for relief request 13R-16 during a teleconference with your staff on March 25, 2014.
F. Diya If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov.
Sincerely, Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-483
Enclosure:
Safety Evaluation cc w/encl: Distribution via Listserv
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST 13R-16 FOR TEMPORARY NON-CODE REPAIR OF THE TRAIN "A" COMPONENT COOLING WATER HEAT EXCHANGER UNION ELECTRIC COMPANY CALLAWAY PLANT. UNIT 1 DOCKET NO. 50-483
1.0 INTRODUCTION
By letter dated March 19, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14079A529), Union Electric Company (dba Ameren Missouri, the licensee) requested relief from certain American Society of Mechanical Engineers (ASME)
Boiler and Pressure Vessel Code (Code) requirements for the Callaway Plant, Unit 1 (Callaway). The scope of the request is limited to the temporary repair of leakage in the train "A" component cooling water (CCW) heat exchanger (EEG01A). In lieu of the IWA-4000 requirements, the alternative will apply provisions of IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," and Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundaries," for installation of a temporary non-Code repair to control leakage from EEG01A.
Although the licensee has already implemented the temporary non-Code repair to control leakage from the subject component prior to the issuance of this safety evaluation (SE), this SE is being issued to document the decision made by the U.S. Nuclear Regulatory Commission (NRC) staff to grant the licensee's request by verbal authorization on March 25, 2014 (ADAMS Accession No. ML14087A210).
2.0 REGULATORY EVALUATION
Pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR) 50.55a(a)(3), alternatives to requirements may be authorized by the NRC if the licensee demonstrates that: (i) the proposed alternatives provide an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. The licensee submitted the subject relief request, pursuant to 10 CFR 50.55a(a)(3)(ii).
Enclosure
3.0 LICENSEE EVALUATION 3.1 Component Affected Train "A" Component Cooling Water Heat Exchanger (EEG01A) tube side manway access, an ASME Class 3 Component.
3.2 ASME Code Requirements for which Relief is Requested The inservice inspection (lSI) Code of record for Callaway Plant for the third ten-year lSI interval is the ASME Code,Section XI 1998 Edition, including 2000 Addenda.
Section C.12 of Chapter 0326 of the NRC Inspection Manual states, in part, that there is no generically approved alternative (non-Code repair) for temporary repair of flaws in a Class 3 vessel (such as EEG01A). The component must be repaired in accordance with the Code, or Code relief must be requested and approved from the NRC in order to apply a non-Code repair.
ASME Code,Section XI requires that repair/replacement activities on ASME Code Class components be performed in accordance with the rules found in Article IWA-4000, "Repair/Replacement Activities." IWA-4133, "Mechanical Clamping Devices used as Piping Pressure Boundary," allows mechanical clamping devices to be used as piping pressure boundary provided the requirements of Mandatory Appendix IX, "Mechanical Clamping Devices for Class 2 and 3 Piping Pressure Boundary," are met. Relief is requested to use IWA-4133 and to apply the provisions of ASME Code,Section XI, Mandatory Appendix IX for a temporary repair to the subject component, heat exchanger EEG01A.
3.3 Duration of Relief Request This relief request for Callaway is applicable to the end of the current fuel cycle, which is scheduled for October 2014.
3.4 Reason for Request On October 14, 2013, the licensee discovered a leak of essential service water (ESW) from the train "A" CCW heat exchanger EEG01A. The leak is due to a flaw from localized pitting and has been analyzed with ultrasonic examination. The bounding size of the flaw has been conservatively estimated to be a pit of a %-inch diameter.
Given the conservative flaw size, the maximum calculated leak rate is 59.4 gallons per minute (gpm). An evaluation (Attachment A to the submittal) of the structural integrity of the subject component with a % inch diameter flaw was done according to ASME Code Case N-705, "Evaluation Criteria for Temporary Acceptance of Degradation in Moderate Energy Class 2 or 3 Vessels and Tanks" (accepted by the NRC and incorporated into Revision 16 of Regulatory Guide 1.147, "lnservice Inspection Code Case Acceptability, ASME Section XI, Division 1").
The evaluation has determined that the flaw responsible for the leakage is acceptable and that structural integrity of EEG01A will be maintained through the current fuel cycle without repair.
If the flaw were to grow larger than ~-inch diameter, the maximum calculated leak rate would be
> 59.4 gallons per minute (gpm), which would reduce the inventory of the ultimate heat sink (UHS) over the 30-day ESW mission time. Compensatory actions have been taken by the licensee to assure the minimum UHS level is maintained above 75.5 percent full in order to provide sufficient inventory to compensate for existing ESW leakage plus the postulated 59.4 gpm loss and keep the UHS and ESW system operable. In an effort to provide additional margin to assure the minimum UHS level, a temporary mechanical clamping device is proposed, which would reduce leakage and would be able to be credited as a pressure boundary in the area of the flaw.
3.5 Licensee's Proposed Alternative to ASME Code IWA-4000 In its letter dated March 19, 2014, the licensee stated, in part, that:
A mechanical clamp will be installed over the leakage location and will act as a credited pressure boundary in the vicinity of the pinhole leak.... A detailed description of the mechanical clamping device and the supporting calculations are supplied in Attachment B [to the submittal].
Until a permanent repair is performed in accordance with IWA-4000 to restore
[heat exchanger] EEG01A to its design condition, the following actions are also being performed to satisfy the ASME Code Case N-705 requirements for monitoring and examination of the flaw.
- Daily leakage monitoring is performed to assure the leakage remains within acceptable limits established in the Code Case N-705 evaluation.
At present, there is no active leakage of ESW through the flaw. Following installation of the mechanical clamping device, this daily monitoring will also provide assurance that integrity of the credited pressure boundary is maintained.
- Ultrasonic examinations are performed quarterly to verify whether the degradation, including growth, continues to meet the acceptable limits established in the Code Case N-705 evaluation. The mechanical clamp pressure block has been designed to allow removal during these periodic examinations to facilitate measurement of the flaw.
3.6 Licensee's Basis for the Proposed Alternative An ASME Code Repair/Replacement of the heat exchanger would require draining of ESW from the CCW heat exchanger, making one ESW train inoperable, and would also make one emergency diesel generator inoperable. This activity would therefore place the plant in Action statements for Technical Specifications 3.7.7, "Component Cooling Water System," 3.7.8, "Essential Service Water System," and 3.8.1, "AC Sources- Operating," each of which requires restoration of the inoperable train within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The Code Repair/Replacement activity on the CCW heat exchanger could last longer than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> and would therefore necessitate a unit shutdown. Cycling the plant to perform an ASME Code repair of heat exchanger EEG01A would create a hardship based on the potential risks associated with unit cycling and any
emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety.
4.0 NRC STAFF EVALUATION The NRC staff reviewed the submittal as a priority due to the operational issues for the unit.
The licensee provided a detailed assessment of the structural integrity of the component according to ASME Code Case N-705 with the temporary repair and without the repair (leaving the assumed %-inch diameter flaw in place). In both cases, the assessment demonstrated that the CCW heat exchanger (EEG01A) can continue to operate until the next refueling outage in October of 2014. Given the postulated gallons per minute ESW leak, a margin still exists between the worst-case condition and the requirements for ESW system operability.
During the coming summer months, the temperature of the ESW system will increase and without a repair, the margin for operability is reduced. In an effort to increase the margin of operability, the proposed alternative would install a temporary mechanical clamping device, which would eliminate the assumed leakage and would be able to be credited as a pressure boundary in the area of the leak. The design of the clamping device follows the requirements of IWA-4133. The licensee has used conservative assumptions regarding the flaw size, stress state, and potential for flaw growth until the next refueling outage, and determined that the postulated flaw would meet the structural margins required by the ASME Code Case N-705 under all normal, upset, emergency, and faulted conditions. Furthermore, the licensee has committed to daily visual inspection for leakage and additional quarterly ultrasonic inspections to demonstrate that the alternative still meets the Code Case N-705 requirements for monitoring and examination of the flaw (pit) that caused the leakage.
The NRC staff has completed its review of the information provided by the licensee and the requirements for use of ASME Code Case N-705. The staff concludes that requiring the licensee to make a permanent Code-required repair to the leaking heat exchanger EEG01A before the next refueling outage would create a hardship based on the potential risks associated with unit cycling and any emergent equipment issues incurred during shutdown and startup evolutions, without a compensating increase in level of quality or safety.
5.0 CONCLUSION
Based on the discussion above, the NRC staff concludes that the alternative proposed in the Relief Request 13R-16, to perform a non-Code repair to the leak found in the train "A" CCW heat exchanger EEG01A is acceptable because compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Therefore, pursuant to 10 CFR 50.55a{a){3)(ii), the staff authorizes the proposed Relief Request 13R-16 for Callaway Plant until the end of Fuel Cycle 20, which is scheduled for October 2014.
All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in this relief request remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector.
Principal Contributor: P. Purtscher, NRR/DE/EVIB Date: September 4, 2014
F. Diya If you have any questions, please contact Fred Lyon at 301-415-2296 or via e-mail at fred.lyon@nrc.gov.
Sincerely, IRA/
Eric R. Oesterle, Acting Chief Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-483
Enclosure:
Safety Evaluation cc w/encl: Distribution via Listserv DISTRIBUTION:
PUBLIC LPL4-1 Reading RidsAcrsAcnw_MaiiCTR Resource RidsNrrPMCallaway Resource RidsNrrLAJBurkhardt Resource RidsRgn4MaiiCenter Resource RidsNrrDeEvib Resource RidsNrrDorllpl4-1 Resource PPurtscher, NRRIDE/EVIB ADAMS Access1on No.: ML14234A451
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NAME Flyon JBurkhardt SRosenberg EOesterle DATE 9/3/14 9/3/14 8/21/14 9/4/14 OFFICIAL RECORD COPY
