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{{#Wiki_filter:}} | {{#Wiki_filter: Mr. Mano Nazar President and Chief Nuclear Officer Nuclear Division NextEra Energy P.O. Box 14000 Juno Beach, FL 33408-0420 December 11, 2015 | ||
SUBJECT: TURKEY POINT NUCLEAR GENERATING UNIT NOS. 3 AND 4 -SAFETY EVALUATION FOR RELIEF REQUEST NO. 15, FOR THE FOURTH 10-YEAR INSERVICE INSPECTION INTERVAL REGARDING THE AMOUNT OF COVERAGE OBTAINED DURING SPECIFIC EXAMINATIONS (CAC NOS. MF5794 AND MF5795) | |||
==Dear Mr. Nazar:== | |||
By letter dated February 13, 2015, as supplemented by letter dated July 8, 2015, Florida Power & Light Company (FPL or the licensee) submitted Relief Request No. 15 for the fourth 10-year inservice inspection (ISi) interval of Turkey Point Nuclear Generating Unit Nos. 3 (Turkey Point Unit 3) and 4 (Turkey Point Unit 4). Pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 55a(g)(5)(iii), the licensee requested the U.S. Nuclear Regulatory Commission (NRC) relief pertaining to the amount of coverage obtained during specific examinations compared to the coverage required by the American Society of Mechanical Engineers (ASME) Code. Based on the review of the submittals, the NRC staff concluded that compliance with the ASME Code coverage requirements is impractical for the configurations identified in the subject relief requests, and that compliance with the specified requirements would result in a burden on FPL. The NRC staff also concluded that the examination coverages obtained by the licensee provide reasonable assurance of the structural integrity of the affected components. Therefore, relief granted pursuant to 10 CFR 55.a(g)(6)(i) is authorized by law and will not endanger life or property or the common defense and security, and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. The relief is granted for the fourth 10-year ISi interval at Turkey Point Unit 3, which began February 22, 2004, and ended February 21, 2014, and for the fourth 10-year ISi interval at Turkey Point Unit 4, which began April 15, 2004, and ended April 14, 2014. The NRC evaluation of the relief requests is documented in the enclosed safety evaluation. All other ASME Code, Section XI requirements for which the request was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. If you have any questions regarding this issue, please contact the project manager, Ms. Audrey L. Klett, at (301) 415-0489 or by e-mail at Audrey.Klett@nrc.gov. Docket Nos. 50-250 and 50-251 | |||
===Enclosure:=== | |||
Safety Evaluation cc w/encl.: Distribution via Listserv | |||
Sincerely,Benjamin G. Beasley, Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST NO. 15 FOR THE FORTH 10-YEAR INSERVICE INSPECTION INTERVAL FLORIDA POWER & LIGHT COMPANY TURKEY POINT NUCLEAR GENERATING UNIT NOS. 3 AND 4 DOCKET NOS. 50-250 AND 50-251 1.0 INTRODUCTION By letter dated February 13, 2015 (Agencywide Documents Access and Management System (ADAMS) Package Accession No. ML 15062A279), as supplemented by letter July 8, 2015 (ADAMS Accession No. ML 15205A317), Florida Power & Light Company (FPL or the licensee) submitted Relief Request (RR) No. 15 for the fourth 10-year inservice inspection (ISi) interval of Turkey Point Nuclear Generating Unit No. 3 (Turkey Point Unit 3) and Turkey Point Nuclear Generating Unit No. 4 (Turkey Point Unit 4). Pursuant to Title 10 of the Code of Federal Regulations (1 O CFR), Part 50, Section 55a(g)(5)(iii), the licensee requested the U.S. Nuclear Regulatory Commission (NRC) relief pertaining to the reactor pressure vessel (RPV) examination requirements of Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). 2.0 REGULATORY EVALUATION The ISi of ASME Code Class 1, 2, and 3 components is performed in accordance with Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components," of the ASME Code and applicable edition and addenda, as required by 10 CFR 50.55a(g). When conformance to these requirements is determined to be impractical, relief may be granted by the NRC pursuant to 10 CFR 50.55a(g)(6)(i). Additionally, pursuant to 10 CFR 50.55a(g)(6)(i), the NRC may impose such alternative requirements, as it determines is authorized by law, that will not endanger life or property or the common defense and security and are otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code, Section XI, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system Enclosure | |||
-2 -pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 1 O CFR 50.55a(a) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed in 10 CFR 50.55a(b)(2). The Code of record for Turkey Point Units 3 and 4 for the fourth 10-year ISi interval is the 1998 Edition Addenda through 2000 Addenda of the ASME Code, Section XI. Pursuant to 10 CFR 50.55a(g)(5)(iv), where an examination requirement by the ASME Code edition or addenda is determined to be impractical by the licensee, the basis for this determination must be submitted for NRC review and approval not later than 12 months after the expiration of the initial or subsequent 120-month inspection interval for which relief is sought. The licensee submitted RR No. 15 on February 13, 2015. Turkey Point Units 3 and 4 fourth 10-year ISi interval ended on February 21, 2014, and April 14, 2014, respectively. Since the licensee submitted RR No. 15 prior to 12 months after the expiration of the fourth 10-year ISi intervals of Turkey Point, Units 3 and 4, the licensee has met the requirement of 10 CFR 50.55a(g)(5)(iv). With respect to examination coverage, "essentially 100 percent" is clarified by ASME Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds," to be greater than 90-percent coverage of the examination volume, or surface area, as applicable. ASME Code Case N-460 has been approved for use by the NRC in Regulatory Guide 1.14 7, Revision 17, "lnservice Inspection Code Case Acceptability, ASME Section XI, Division 1." 3.0 TECHNICAL EVALUATION 3.1 ASME Code Components Affected and Applicable Code Edition and Addenda For the fourth 10-year interval, the ASME Code of record for Turkey Point Unit 3 and Unit 4 is the 1998 Edition with Addenda through 2000 of the ASME Boiler and Pressure Vessel Code, Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components" as modified by 10 CFR 50.55a. The 1998 Edition with Addenda through 2000 was utilized for ASME Section XI, Appendix VIII. The ASME Code components affected are the Class 1 pressure retaining welds in the RPV. The licensee requested relief for the ASME Code Class 1 components listed in Table 1. The ASME Code examination requirements are also shown in Table 1. | |||
-3 -Table 1. ASME Code Examination Categories and Examination Item No. <1> Component Item Examination Category <1> Name Description <1l Requirements <1l 3-WR-31 Circumferential Essentially 100% (2l volumetric B-A 81 .11 4-WR-31 Shell Weld examination of all circumferential shell welds 3-WR-18 Shell-to-Flange Essentially 100% (2J volumetric B-A 81.30 examination of the shell-to-4-WR-18 Weld flange weld Essentially 100% (2) volumetric B-G-1 86.40 3-Lig-1 thru 58 Threads in examination of the 1-inch 4-Lig-1 thru 58 Flange annular surface of flange surrounding each stud hole Notes: (1) Examination categories, item numbers, item descriptions, and examination requirements are from Table IWB-2500-1 of Section XI of the ASME Code. (2) "Essentially 100%" is clarified by ASME Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds," to be greater than 90% coverage of the examination volume, or surface area, as applicable. 3.2 Licensee's RR No. 15 Pursuant to 1 O CFR 50.55a(g)(5)(iii), the licensee determined that conformance with essentially 100% examination coverage requirements of Section XI of the ASME Code (as clarified by ASME Code Case N-460 to be 90% coverage) is impractical for the RPV components listed in Table 1. The percent examination coverages achieved by the licensee are shown in Table 2. Table 2. Examination Coverage Achieved Examination . Item No. Component Percent Examination Category Name Coverage Achieved B-A 81 .11 3-WR-31 85% 4-WR-31 B-A 81.30 3-WR-18 75% 4-WR-18 B-G-1 86.40 3-Lig-1 thru 58 84.67% 4-Lig-1 thru 58 3.3 Licensee's Basis for RR No. 15 FPL stated that due to the permanent attachments and design configuration of the RPV that it is impractical to meet the ASME Code examination coverage requirements. Examination of welds 3-WR-31 and 4-WR-31 were limited due to interference from the core support lugs. Examination of welds 3-WR-18 and 4-WR-18 were limited due to the keyways and irradiation | |||
-4 -slots. Examination of the RPV threads in the flange, 3-Lig-1 through 58 and 4-Lig-1 through 58, were limited due to the 0-ring groove machined into the flange surface, limiting the area for transducer placement for the examination. Removing these obstructions and geometric limitations would require modification of the RPV, which would mean significant work, increased radiation exposure, and/or damage to the plant. In its submittal dated February 13, 2015, the licensee stated that in addition to the ASME Code required ultrasonic (UT) examinations, the interior of the RPVs, including welded attachments, received visual (VT) examinations in accordance with Table IW8-2500-1, "Examination Categories" category 8-N-1, 8-N-2 and 8-N-3 of Section XI of the ASME Code. The VT examinations revealed no relevant indications. 3.4 Licensee's Proposed Alternatives 1. Periodic system pressure tests in accordance with ASME Code Section XI Category 8-P, Table IW8-2500-1. 2. Conduct UT examinations to the maximum extent possible. 3.5 NRC Staff Evaluation The NRC staff evaluated FPL's RR No. 15 from essentially 100-percent examination coverage requirements of Section XI of the ASME Code on the basis of impracticality, pursuant to 10 CFR 50.55a(g)(5)(iii) for the subject RPV components. The following paragraphs provide details of the evaluation. 3.5: 1 RPV Lower Shell to Lower Head Ring, Circumferential Shell Welds (3-WR-31 and 4-WR-31) ASME Code, Section XI, Examination Category 8-A, Item 81 .11 The examination coverage for welds 3-WR-31 and 4-WR-31 was less than essentially 100-percent due to scanning limitations caused by the core support lugs. As such, obtaining the ASME Code required examination volumes would require significant modification of the RPVs, which imposes a burden. FPL indicated in the submittal dated February 13, 2015, that the limitation is also due to the presence of instrumentation tubes. On June 4, 2015, the NRC staff issued request for additional information (RAI) (ADAMS Accession No. ML 15155A919). In RAI 1 a, the NRC staff requested the licensee to confirm that the limited coverage of welds 3-WR-31 and 4-WR-31 was due to core support lugs, not instrumentation tubes. In its supplemental letter dated July 8, 2015, the licensee responded that "instrumentation tubes" was a typographical error in its February 13, 2015, submittal, and that the limited coverage of welds 3-WR-31 and 4-WR-31 was due only to the core support lugs. The licensee also indicated that the core support lugs are also known as "core guide lugs." The NRC staff finds these responses to be acceptable. The licensee stated that for welds 3-WR-31 and 4-WR-31, access was restricted by 15-percent and that the remaining 85-percent examination volume was examined with techniques that have been qualified in accordance with Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code with Addenda through 2000, as implemented by the industry's Performance Demonstration Initiative (POI). The welds were examined to the maximum extent possible, from both sides of the welds, scanning both parallel and perpendicular to the welds. | |||
-5 -For weld 3-WR-31, the UT examination revealed no indications. For weld 4-WR-31, the UT examination revealed four acceptable small fabrication flaws in the weld. In RAI 2a, the NRC staff requested the licensee to confirm that the subsurface fabrication flaws found in weld 4-WR-31 met the acceptance criteria of Table IWB-3510-1, "Allowable Planar Flaws" of Section XI of the ASME Code. In its July 8, 2015, response, the licensee indicated that the acceptance criteria of Table IWB-3510-1 were met. The NRC staff finds this response to be acceptable. The NRC staff noted that the examination diagrams for welds 3-WR-31 and 4-WR-31 provided in the licensee's February 13, 2015, submittal were not clear. Therefore, in RAI 1 b, the NRC staff requested the licensee to provide inspection diagrams using guidance from a presentation given in a public meeting held by the industry and the NRC on January 13 -15, 2015 (ADAMS Accession No. ML 15013A266). In its July 8, 2015, response, the licensee provided an examination summary table and inspection diagrams that contain the ASME Code, Section XI required examination volume, the scan angles and axial distances of the search units from the subject welds, and the inspection volumes achieved in both the axial and circumferential directions. The examination summary table and inspection diagrams provided by the licensee enabled the NRC staff to confirm the examination volumes achieved and verify the scanning limitations. The NRC staff finds this response to be acceptable. The licensee indicated that there is no plant-specific or industry experience regarding potential degradation mechanisms specific to welds 3-WR-31 and 4-WR-31. Based on the examination coverage obtained for welds 3-WR-31 and 4-WR-31, if significant service-induced degradation were occurring, the NRC staff concluded that there is reasonable assurance that evidence of degradation would be detected by the examinations. The NRC staff noted that a relief request was not submitted during the previous (third) 10-year ISi interval for welds 3-WR-31 and 4-WR-31. Because the design configuration of the RPV has not changed since original plant construction, in RAI 3, the NRC staff requested the licensee to confirm whether a relief request was previously submitted for the third 10-year ISi interval for welds 3-WR-31 and 4-WR-31, or to provide the reasons for not previously requesting relief. In its July 8, 2015, response, the licensee stated that a relief request was not submitted in the third 10-year ISi interval for welds 3-WR-31 and 4-WR-31, because volumetric examination coverage of greater than 90% was achieved. The licensee further stated that the process used to calculate the examination coverage for welds with both single-side and dual-side access was refined over the last 10 years, and that the result of this refinement was a more conservative approach that results in reduced examination coverage (hence, less than 90-percent examination coverage for the fourth 10-year ISi interval). The licensee stated that the reduced examination coverage reflects the expectations of 10 CFR 50.55a(b)(2)(xv)(G) regarding application of the examination methodology of Appendix VIII of Section XI of the ASME Code. The NRC staff finds this response to be acceptable. Based on the above discussion, the NRC staff determined that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee. The NRC staff also determined that the UT examinations performed to the maximum extent possible and VT examinations provide reasonable assurance of the structural integrity of the subject welds. | |||
-6 -3.5.2 RPV Upper Shell-to-Flange Welds (3-WR-18 and 4-WR-18) ASME Code, Section XI, Examination Category B-A, Item 81 .30 The examination coverage for welds 3-WR-18 and 4-WR-18 was less than essentially 100-percent due to scanning limitations caused by the keyways and irradiation slots. As such, obtaining the ASME Code required examination volumes would require significant modification of the RPVs, which imposes a burden. FPL stated that for welds 3-WR-18 and 4-WR-18, access was restricted by 25-percent and that the remaining 75-percent examination volume was examined with techniques that have been qualified in accordance with Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code, with Addenda through 2000, as implemented by the industry's POI. The NRC staff noted that Appendix I, Article l-2110(b) of Section XI of the ASME Code requires shell-to-flange welds, such as 3-WR-18 and 4-WR-18, to be examined in accordance with Article 4 of Section V of the ASME Code. In a letter dated November 29, 2013 (ADAMS Accession No. ML 13260A493), the NRC approved the use of the examination methods in Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code with Addenda through 2000, for shell-to-flange welds 3-WR-18 and 4-WR-18 for the fourth 10-year ISi interval. The welds were examined to the maximum extent possible, from both sides of the welds, scanning both parallel and perpendicular to the welds. For weld 3-WR-18, the UT examination revealed three acceptable small fabrication flaws. For weld 4-WR-18, the UT examination revealed twelve acceptable srryall fabrication flaws. In RAI 2b, the NRC staff requested the licensee to confirm that the subsurface fabrication flaws found in these welds met the acceptance criteria of Table IWB-3510-1, "Allowable Planar Flaws" of Section XI of the ASME Code. In its July 8, 2015, response, the licensee stated that the acceptance criteria of Table IWB-3510-1 were met. The NRC staff finds this response to be acceptable. The NRC staff noted that the examination diagrams for welds 3-WR-18 and 4-WR-18 provided in the licensee's February 13, 2015, submittal were not clear. Therefore, in RAI 1 c, the NRC staff requested the licensee to provide inspection diagrams using guidance from a presentation given in a public meeting held by the industry and the NRC on January 13 -15, 2015 (ADAMS Accession No. ML 15013A266). In its July 8, 2015, response, the licensee provided an examination summary table and inspection diagrams that contain the required ASME Code, Section XI examination volume, the scan angles and axial distances of the search units from the subject weld, and the examination volumes achieved in both the axial and circumferential directions. The examination summary table and inspection diagrams provided by the licensee enabled the NRC staff to confirm the examination volumes achieved and verify the scanning limitations. The NRC staff finds this response to be acceptable. The licensee indicated that there is no plant-specific or industry experience regarding potential degradation mechanisms specific to welds 3-WR-18 and 4-WR-18. Based on the examination coverage obtained for welds 3-WR-18 and 4-WR-18, if significant service-induced degradation were occurring, the NRC staff concluded that there is reasonable assurance that evidence of it would be detected by the examinations. The NRC staff noted that the subsurface flaws that were reported for welds 3-WR-18, and 4-WR-18 during the fourth 10-year ISi interval, but not during the third 10-year ISi interval, as | |||
-7 -documented in Relief Request 1A (ADAMS Accession No. ML060520631). Therefore, in RAI 4, the NRC staff requested the licensee to explain why subsurface flaws were detected during the fourth 10-year ISi interval and not in the third 10-year ISi interval. In its July 8, 2015 response, the licensee responded that in recent years the approach for the recording of flaws has become more conservative. The licensee also made a comparison of the subsurface flaws identified during the fourth 10-year ISi interval with examination data for the third 10-year ISi interval and concluded that all flaws remained essentially unchanged. The licensee stated that the qualified examination procedures have criteria that must be met for an indication (in this context is synonymous with "flaw") to be recorded. The licensee stated that there were flaws that were very near the recording threshold and that during the third 10-year ISi interval, the flaws were slightly below the recording threshold. However, due to slight variances of the examinations in the fourth 10-year ISi interval from those in the previous 10-year ISi interval, the licensee stated that, during the fourth 10-year ISi interval, those flaws were at or slightly over the recording threshold and were therefore recorded. The NRC staff finds this explanation to be acceptable. Based on the above discussion, the NRC staff determined that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee. The NRC staff also determined that the UT examinations performed to the maximum extent possible and VT examinations provide reasonable assurance of the structural integrity of the subject welds. 3.5.3 RPV Threads in Flange (3-Lig-1 through 58 and 4-Lig-1 through 58) ASME Code, Section XI, Examination Category B-G-1, Item 86.40 In its February 13, 2015 submittal, FPL stated that the examination coverage for the RPV flange threads 3-Lig-1 through 58 and 4-Lig-1 through 58 was less than essentially 100-percent due to scanning limitations caused by the 0-ring groove machined into the flange surfaces, which limited the area for transducer placement. As such, obtaining the ASME Code required examination volume would require significant modification of the RPVs, which imposes a burden on the licensee. The licensee further stated that for welds 3-Lig-1 through 58 and 4-Lig-1 through 58, access was restricted by 15.33-percent and that the remaining 84.67-percent examination volume was examined with techniques that meet the ASME Code requirements. The UT examinations did not reveal any recordable or reportable flaws. The NRC staff noted that these examination results are unchanged from the examination results of the third 10-year ISi interval, which the NRC staff previously found to be acceptable (ADAMS Accession No. ML063420372). Therefore, the NRC staff concluded that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee, and that the UT examinations that were performed to the maximum extent possible provide reasonable assurance of the structural integrity of the RPV flange threads. 3.5.4 Compensatory Measures The NRC staff noted that FPL's "proposed alternatives," listed in Section 3.4 of this safety evaluation, are not proposals for alternatives pursuant to 10 CFR 50.55a(z) (formerly 10 CFR 50.55a(a)(3)). Periodic system pressure testing of the RPV pressure retaining boundary in accordance with Examination Category B-P of Table IWB-2500-1 of Section XI of the ASME Code is required per 10 CFR 50.55a(g)(4). Conducting UT examinations to the maximum extent possible are discussed in the preceding paragraphs for each of the RPV components addressed | |||
-8 -in the licensee's February 13, 2015, submittal. Both are regarded as compensatory measures due to the scanning limitations. The Examination Category B-P system pressure test includes VT-2 for evidence of leakage, which provides reasonable assurance of leak tightness. Additionally, the licensee stated that in Turkey Point Unit 4, leakage monitoring is provided by the reactor containment sump inlet flow monitoring system, which has high level and alert status alarms in the control room, and that monitoring is performed at least once every 12 hours in accordance with the plant Technical Specifications. Collectively, the VT-2 examinations for both units, and the leakage monitoring system for Turkey Point Unit 4, provide reasonable assurance of leak tightness, and of leak detection should leakage occur. 3.5.5 Evaluation of Impracticality It is not possible to obtain UT examination of greater than 90-percent of the required examination volume due to interference caused by configuration and/or permanent attachments. Examinations were performed to the maximum extent possible. The UT techniques for each weld or surface were reviewed to determine if additional coverage could be achieved. For the welds or surfaces listed above, it was not possible to remove the obstruction without significant work, increased radiation exposure, and/or damage to the plant; therefore, imposing greater than 90-percent examination would be a burden for FPL. 3.5.6 Structural Integrity or Leak Tightness FPL performed 85-percent UT examination for Examination Category B-A, Item B1 .11, 75-percent UT examination for Examination Category B-A, Item B1 .30, and 84.67-percent UT examination for Examination Category B-G-1, Item B6.40. The accessible areas of the RPV shell weld were examined with personnel, equipment and procedures that were qualified by demonstration in accordance with Supplements 4 and 6 of the 1998 Edition up to and including the 2000 Addenda of the ASME Code, Section XI, Appendix VIII, using the POI protocol. These examinations were performed by the licensee from both sides of the welds, scanning both parallel and perpendicular to the weld to the maximum extent possible. FPL performed VT examination the interior of the reactor vessel, including welded attachments, in accordance with Table IWB-2500-1, Examination Categories B-N-1, B-N-2 and B-N-3. The VT examinations revealed no relevant indications according to the licensee. Based on the UT and VT examinations performed by FPL, the NRC staff has reasonable assurance of structural integrity or leak tightness of the RPV welds. 4.0 CONCLUSION Based on the review of the submittals, the NRC staff concluded that compliance with the ASME Code coverage requirements is impractical for the configurations identified in the subject relief requests, and that compliance with the specified requirements would result in a burden on FPL. The NRC staff also concluded that the examination coverages obtained by the licensee provide reasonable assurance of the structural integrity of the affected components. Therefore, relief | |||
-9 -granted pursuant to 10 CFR 55.a(g)(6)(i) is authorized by law and will not endanger life or property or the common defense and security, and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. Therefore, the NRC staff grants relief for the examinations of the RPV Circumferential Shell Welds (3-WR-31 and 4-WR-31), RPV Shell-to-Flange Welds (3-WR-18 and 4-WR-18), and RPV Threads in Flange (3-Lig-1 through 58 and 4-Lig-1 through 58) contained in RR No. 15 for the Turkey Point, Units 3 and 4 fourth 10-year ISi interval. The relief is granted for the fourth 10-year ISi interval at Turkey Point Unit 3, which began February 22, 2004, and ended February 21, 2014, and for the fourth 10-year ISi interval at Turkey Point Unit 4, which began April 15, 2004, and ended April 14, 2014. All other ASME Code, Section XI requirements for which relief was not specifically requested and approved in the subject request for relief remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. Principal Contributors: David Dijamco, Gary Stevens, and Carol Nove Date: December 11, 2015}} |
Revision as of 22:26, 19 March 2018
ML15328A240 | |
Person / Time | |
---|---|
Site: | Turkey Point ![]() |
Issue date: | 12/11/2015 |
From: | Beasley B G Plant Licensing Branch II |
To: | Nazar M Nextera Energy |
Lamb J G, NRR/DORL, 415-3100 | |
References | |
CAC MF5794, CAC MF5795 | |
Download: ML15328A240 (12) | |
Text
Mr. Mano Nazar President and Chief Nuclear Officer Nuclear Division NextEra Energy P.O. Box 14000 Juno Beach, FL 33408-0420 December 11, 2015
SUBJECT: TURKEY POINT NUCLEAR GENERATING UNIT NOS. 3 AND 4 -SAFETY EVALUATION FOR RELIEF REQUEST NO. 15, FOR THE FOURTH 10-YEAR INSERVICE INSPECTION INTERVAL REGARDING THE AMOUNT OF COVERAGE OBTAINED DURING SPECIFIC EXAMINATIONS (CAC NOS. MF5794 AND MF5795)
Dear Mr. Nazar:
By letter dated February 13, 2015, as supplemented by letter dated July 8, 2015, Florida Power & Light Company (FPL or the licensee) submitted Relief Request No. 15 for the fourth 10-year inservice inspection (ISi) interval of Turkey Point Nuclear Generating Unit Nos. 3 (Turkey Point Unit 3) and 4 (Turkey Point Unit 4). Pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 55a(g)(5)(iii), the licensee requested the U.S. Nuclear Regulatory Commission (NRC) relief pertaining to the amount of coverage obtained during specific examinations compared to the coverage required by the American Society of Mechanical Engineers (ASME) Code. Based on the review of the submittals, the NRC staff concluded that compliance with the ASME Code coverage requirements is impractical for the configurations identified in the subject relief requests, and that compliance with the specified requirements would result in a burden on FPL. The NRC staff also concluded that the examination coverages obtained by the licensee provide reasonable assurance of the structural integrity of the affected components. Therefore, relief granted pursuant to 10 CFR 55.a(g)(6)(i) is authorized by law and will not endanger life or property or the common defense and security, and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. The relief is granted for the fourth 10-year ISi interval at Turkey Point Unit 3, which began February 22, 2004, and ended February 21, 2014, and for the fourth 10-year ISi interval at Turkey Point Unit 4, which began April 15, 2004, and ended April 14, 2014. The NRC evaluation of the relief requests is documented in the enclosed safety evaluation. All other ASME Code,Section XI requirements for which the request was not specifically requested and approved remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. If you have any questions regarding this issue, please contact the project manager, Ms. Audrey L. Klett, at (301) 415-0489 or by e-mail at Audrey.Klett@nrc.gov. Docket Nos. 50-250 and 50-251
Enclosure:
Safety Evaluation cc w/encl.: Distribution via Listserv
Sincerely,Benjamin G. Beasley, Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST NO. 15 FOR THE FORTH 10-YEAR INSERVICE INSPECTION INTERVAL FLORIDA POWER & LIGHT COMPANY TURKEY POINT NUCLEAR GENERATING UNIT NOS. 3 AND 4 DOCKET NOS. 50-250 AND 50-251 1.0 INTRODUCTION By letter dated February 13, 2015 (Agencywide Documents Access and Management System (ADAMS) Package Accession No. ML 15062A279), as supplemented by letter July 8, 2015 (ADAMS Accession No. ML 15205A317), Florida Power & Light Company (FPL or the licensee) submitted Relief Request (RR) No. 15 for the fourth 10-year inservice inspection (ISi) interval of Turkey Point Nuclear Generating Unit No. 3 (Turkey Point Unit 3) and Turkey Point Nuclear Generating Unit No. 4 (Turkey Point Unit 4). Pursuant to Title 10 of the Code of Federal Regulations (1 O CFR), Part 50, Section 55a(g)(5)(iii), the licensee requested the U.S. Nuclear Regulatory Commission (NRC) relief pertaining to the reactor pressure vessel (RPV) examination requirements of Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). 2.0 REGULATORY EVALUATION The ISi of ASME Code Class 1, 2, and 3 components is performed in accordance with Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components," of the ASME Code and applicable edition and addenda, as required by 10 CFR 50.55a(g). When conformance to these requirements is determined to be impractical, relief may be granted by the NRC pursuant to 10 CFR 50.55a(g)(6)(i). Additionally, pursuant to 10 CFR 50.55a(g)(6)(i), the NRC may impose such alternative requirements, as it determines is authorized by law, that will not endanger life or property or the common defense and security and are otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system Enclosure
-2 -pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 1 O CFR 50.55a(a) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed in 10 CFR 50.55a(b)(2). The Code of record for Turkey Point Units 3 and 4 for the fourth 10-year ISi interval is the 1998 Edition Addenda through 2000 Addenda of the ASME Code,Section XI. Pursuant to 10 CFR 50.55a(g)(5)(iv), where an examination requirement by the ASME Code edition or addenda is determined to be impractical by the licensee, the basis for this determination must be submitted for NRC review and approval not later than 12 months after the expiration of the initial or subsequent 120-month inspection interval for which relief is sought. The licensee submitted RR No. 15 on February 13, 2015. Turkey Point Units 3 and 4 fourth 10-year ISi interval ended on February 21, 2014, and April 14, 2014, respectively. Since the licensee submitted RR No. 15 prior to 12 months after the expiration of the fourth 10-year ISi intervals of Turkey Point, Units 3 and 4, the licensee has met the requirement of 10 CFR 50.55a(g)(5)(iv). With respect to examination coverage, "essentially 100 percent" is clarified by ASME Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds," to be greater than 90-percent coverage of the examination volume, or surface area, as applicable. ASME Code Case N-460 has been approved for use by the NRC in Regulatory Guide 1.14 7, Revision 17, "lnservice Inspection Code Case Acceptability, ASME Section XI, Division 1." 3.0 TECHNICAL EVALUATION 3.1 ASME Code Components Affected and Applicable Code Edition and Addenda For the fourth 10-year interval, the ASME Code of record for Turkey Point Unit 3 and Unit 4 is the 1998 Edition with Addenda through 2000 of the ASME Boiler and Pressure Vessel Code,Section XI, "Rules for lnservice Inspection of Nuclear Power Plant Components" as modified by 10 CFR 50.55a. The 1998 Edition with Addenda through 2000 was utilized for ASME Section XI, Appendix VIII. The ASME Code components affected are the Class 1 pressure retaining welds in the RPV. The licensee requested relief for the ASME Code Class 1 components listed in Table 1. The ASME Code examination requirements are also shown in Table 1.
-3 -Table 1. ASME Code Examination Categories and Examination Item No. <1> Component Item Examination Category <1> Name Description <1l Requirements <1l 3-WR-31 Circumferential Essentially 100% (2l volumetric B-A 81 .11 4-WR-31 Shell Weld examination of all circumferential shell welds 3-WR-18 Shell-to-Flange Essentially 100% (2J volumetric B-A 81.30 examination of the shell-to-4-WR-18 Weld flange weld Essentially 100% (2) volumetric B-G-1 86.40 3-Lig-1 thru 58 Threads in examination of the 1-inch 4-Lig-1 thru 58 Flange annular surface of flange surrounding each stud hole Notes: (1) Examination categories, item numbers, item descriptions, and examination requirements are from Table IWB-2500-1 of Section XI of the ASME Code. (2) "Essentially 100%" is clarified by ASME Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds," to be greater than 90% coverage of the examination volume, or surface area, as applicable. 3.2 Licensee's RR No. 15 Pursuant to 1 O CFR 50.55a(g)(5)(iii), the licensee determined that conformance with essentially 100% examination coverage requirements of Section XI of the ASME Code (as clarified by ASME Code Case N-460 to be 90% coverage) is impractical for the RPV components listed in Table 1. The percent examination coverages achieved by the licensee are shown in Table 2. Table 2. Examination Coverage Achieved Examination . Item No. Component Percent Examination Category Name Coverage Achieved B-A 81 .11 3-WR-31 85% 4-WR-31 B-A 81.30 3-WR-18 75% 4-WR-18 B-G-1 86.40 3-Lig-1 thru 58 84.67% 4-Lig-1 thru 58 3.3 Licensee's Basis for RR No. 15 FPL stated that due to the permanent attachments and design configuration of the RPV that it is impractical to meet the ASME Code examination coverage requirements. Examination of welds 3-WR-31 and 4-WR-31 were limited due to interference from the core support lugs. Examination of welds 3-WR-18 and 4-WR-18 were limited due to the keyways and irradiation
-4 -slots. Examination of the RPV threads in the flange, 3-Lig-1 through 58 and 4-Lig-1 through 58, were limited due to the 0-ring groove machined into the flange surface, limiting the area for transducer placement for the examination. Removing these obstructions and geometric limitations would require modification of the RPV, which would mean significant work, increased radiation exposure, and/or damage to the plant. In its submittal dated February 13, 2015, the licensee stated that in addition to the ASME Code required ultrasonic (UT) examinations, the interior of the RPVs, including welded attachments, received visual (VT) examinations in accordance with Table IW8-2500-1, "Examination Categories" category 8-N-1, 8-N-2 and 8-N-3 of Section XI of the ASME Code. The VT examinations revealed no relevant indications. 3.4 Licensee's Proposed Alternatives 1. Periodic system pressure tests in accordance with ASME Code Section XI Category 8-P, Table IW8-2500-1. 2. Conduct UT examinations to the maximum extent possible. 3.5 NRC Staff Evaluation The NRC staff evaluated FPL's RR No. 15 from essentially 100-percent examination coverage requirements of Section XI of the ASME Code on the basis of impracticality, pursuant to 10 CFR 50.55a(g)(5)(iii) for the subject RPV components. The following paragraphs provide details of the evaluation. 3.5: 1 RPV Lower Shell to Lower Head Ring, Circumferential Shell Welds (3-WR-31 and 4-WR-31) ASME Code,Section XI, Examination Category 8-A, Item 81 .11 The examination coverage for welds 3-WR-31 and 4-WR-31 was less than essentially 100-percent due to scanning limitations caused by the core support lugs. As such, obtaining the ASME Code required examination volumes would require significant modification of the RPVs, which imposes a burden. FPL indicated in the submittal dated February 13, 2015, that the limitation is also due to the presence of instrumentation tubes. On June 4, 2015, the NRC staff issued request for additional information (RAI) (ADAMS Accession No. ML 15155A919). In RAI 1 a, the NRC staff requested the licensee to confirm that the limited coverage of welds 3-WR-31 and 4-WR-31 was due to core support lugs, not instrumentation tubes. In its supplemental letter dated July 8, 2015, the licensee responded that "instrumentation tubes" was a typographical error in its February 13, 2015, submittal, and that the limited coverage of welds 3-WR-31 and 4-WR-31 was due only to the core support lugs. The licensee also indicated that the core support lugs are also known as "core guide lugs." The NRC staff finds these responses to be acceptable. The licensee stated that for welds 3-WR-31 and 4-WR-31, access was restricted by 15-percent and that the remaining 85-percent examination volume was examined with techniques that have been qualified in accordance with Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code with Addenda through 2000, as implemented by the industry's Performance Demonstration Initiative (POI). The welds were examined to the maximum extent possible, from both sides of the welds, scanning both parallel and perpendicular to the welds.
-5 -For weld 3-WR-31, the UT examination revealed no indications. For weld 4-WR-31, the UT examination revealed four acceptable small fabrication flaws in the weld. In RAI 2a, the NRC staff requested the licensee to confirm that the subsurface fabrication flaws found in weld 4-WR-31 met the acceptance criteria of Table IWB-3510-1, "Allowable Planar Flaws" of Section XI of the ASME Code. In its July 8, 2015, response, the licensee indicated that the acceptance criteria of Table IWB-3510-1 were met. The NRC staff finds this response to be acceptable. The NRC staff noted that the examination diagrams for welds 3-WR-31 and 4-WR-31 provided in the licensee's February 13, 2015, submittal were not clear. Therefore, in RAI 1 b, the NRC staff requested the licensee to provide inspection diagrams using guidance from a presentation given in a public meeting held by the industry and the NRC on January 13 -15, 2015 (ADAMS Accession No. ML 15013A266). In its July 8, 2015, response, the licensee provided an examination summary table and inspection diagrams that contain the ASME Code,Section XI required examination volume, the scan angles and axial distances of the search units from the subject welds, and the inspection volumes achieved in both the axial and circumferential directions. The examination summary table and inspection diagrams provided by the licensee enabled the NRC staff to confirm the examination volumes achieved and verify the scanning limitations. The NRC staff finds this response to be acceptable. The licensee indicated that there is no plant-specific or industry experience regarding potential degradation mechanisms specific to welds 3-WR-31 and 4-WR-31. Based on the examination coverage obtained for welds 3-WR-31 and 4-WR-31, if significant service-induced degradation were occurring, the NRC staff concluded that there is reasonable assurance that evidence of degradation would be detected by the examinations. The NRC staff noted that a relief request was not submitted during the previous (third) 10-year ISi interval for welds 3-WR-31 and 4-WR-31. Because the design configuration of the RPV has not changed since original plant construction, in RAI 3, the NRC staff requested the licensee to confirm whether a relief request was previously submitted for the third 10-year ISi interval for welds 3-WR-31 and 4-WR-31, or to provide the reasons for not previously requesting relief. In its July 8, 2015, response, the licensee stated that a relief request was not submitted in the third 10-year ISi interval for welds 3-WR-31 and 4-WR-31, because volumetric examination coverage of greater than 90% was achieved. The licensee further stated that the process used to calculate the examination coverage for welds with both single-side and dual-side access was refined over the last 10 years, and that the result of this refinement was a more conservative approach that results in reduced examination coverage (hence, less than 90-percent examination coverage for the fourth 10-year ISi interval). The licensee stated that the reduced examination coverage reflects the expectations of 10 CFR 50.55a(b)(2)(xv)(G) regarding application of the examination methodology of Appendix VIII of Section XI of the ASME Code. The NRC staff finds this response to be acceptable. Based on the above discussion, the NRC staff determined that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee. The NRC staff also determined that the UT examinations performed to the maximum extent possible and VT examinations provide reasonable assurance of the structural integrity of the subject welds.
-6 -3.5.2 RPV Upper Shell-to-Flange Welds (3-WR-18 and 4-WR-18) ASME Code,Section XI, Examination Category B-A, Item 81 .30 The examination coverage for welds 3-WR-18 and 4-WR-18 was less than essentially 100-percent due to scanning limitations caused by the keyways and irradiation slots. As such, obtaining the ASME Code required examination volumes would require significant modification of the RPVs, which imposes a burden. FPL stated that for welds 3-WR-18 and 4-WR-18, access was restricted by 25-percent and that the remaining 75-percent examination volume was examined with techniques that have been qualified in accordance with Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code, with Addenda through 2000, as implemented by the industry's POI. The NRC staff noted that Appendix I, Article l-2110(b) of Section XI of the ASME Code requires shell-to-flange welds, such as 3-WR-18 and 4-WR-18, to be examined in accordance with Article 4 of Section V of the ASME Code. In a letter dated November 29, 2013 (ADAMS Accession No. ML 13260A493), the NRC approved the use of the examination methods in Supplements 4 and 6 of Appendix VIII to Section XI of the 1998 Edition of the ASME Code with Addenda through 2000, for shell-to-flange welds 3-WR-18 and 4-WR-18 for the fourth 10-year ISi interval. The welds were examined to the maximum extent possible, from both sides of the welds, scanning both parallel and perpendicular to the welds. For weld 3-WR-18, the UT examination revealed three acceptable small fabrication flaws. For weld 4-WR-18, the UT examination revealed twelve acceptable srryall fabrication flaws. In RAI 2b, the NRC staff requested the licensee to confirm that the subsurface fabrication flaws found in these welds met the acceptance criteria of Table IWB-3510-1, "Allowable Planar Flaws" of Section XI of the ASME Code. In its July 8, 2015, response, the licensee stated that the acceptance criteria of Table IWB-3510-1 were met. The NRC staff finds this response to be acceptable. The NRC staff noted that the examination diagrams for welds 3-WR-18 and 4-WR-18 provided in the licensee's February 13, 2015, submittal were not clear. Therefore, in RAI 1 c, the NRC staff requested the licensee to provide inspection diagrams using guidance from a presentation given in a public meeting held by the industry and the NRC on January 13 -15, 2015 (ADAMS Accession No. ML 15013A266). In its July 8, 2015, response, the licensee provided an examination summary table and inspection diagrams that contain the required ASME Code,Section XI examination volume, the scan angles and axial distances of the search units from the subject weld, and the examination volumes achieved in both the axial and circumferential directions. The examination summary table and inspection diagrams provided by the licensee enabled the NRC staff to confirm the examination volumes achieved and verify the scanning limitations. The NRC staff finds this response to be acceptable. The licensee indicated that there is no plant-specific or industry experience regarding potential degradation mechanisms specific to welds 3-WR-18 and 4-WR-18. Based on the examination coverage obtained for welds 3-WR-18 and 4-WR-18, if significant service-induced degradation were occurring, the NRC staff concluded that there is reasonable assurance that evidence of it would be detected by the examinations. The NRC staff noted that the subsurface flaws that were reported for welds 3-WR-18, and 4-WR-18 during the fourth 10-year ISi interval, but not during the third 10-year ISi interval, as
-7 -documented in Relief Request 1A (ADAMS Accession No. ML060520631). Therefore, in RAI 4, the NRC staff requested the licensee to explain why subsurface flaws were detected during the fourth 10-year ISi interval and not in the third 10-year ISi interval. In its July 8, 2015 response, the licensee responded that in recent years the approach for the recording of flaws has become more conservative. The licensee also made a comparison of the subsurface flaws identified during the fourth 10-year ISi interval with examination data for the third 10-year ISi interval and concluded that all flaws remained essentially unchanged. The licensee stated that the qualified examination procedures have criteria that must be met for an indication (in this context is synonymous with "flaw") to be recorded. The licensee stated that there were flaws that were very near the recording threshold and that during the third 10-year ISi interval, the flaws were slightly below the recording threshold. However, due to slight variances of the examinations in the fourth 10-year ISi interval from those in the previous 10-year ISi interval, the licensee stated that, during the fourth 10-year ISi interval, those flaws were at or slightly over the recording threshold and were therefore recorded. The NRC staff finds this explanation to be acceptable. Based on the above discussion, the NRC staff determined that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee. The NRC staff also determined that the UT examinations performed to the maximum extent possible and VT examinations provide reasonable assurance of the structural integrity of the subject welds. 3.5.3 RPV Threads in Flange (3-Lig-1 through 58 and 4-Lig-1 through 58) ASME Code,Section XI, Examination Category B-G-1, Item 86.40 In its February 13, 2015 submittal, FPL stated that the examination coverage for the RPV flange threads 3-Lig-1 through 58 and 4-Lig-1 through 58 was less than essentially 100-percent due to scanning limitations caused by the 0-ring groove machined into the flange surfaces, which limited the area for transducer placement. As such, obtaining the ASME Code required examination volume would require significant modification of the RPVs, which imposes a burden on the licensee. The licensee further stated that for welds 3-Lig-1 through 58 and 4-Lig-1 through 58, access was restricted by 15.33-percent and that the remaining 84.67-percent examination volume was examined with techniques that meet the ASME Code requirements. The UT examinations did not reveal any recordable or reportable flaws. The NRC staff noted that these examination results are unchanged from the examination results of the third 10-year ISi interval, which the NRC staff previously found to be acceptable (ADAMS Accession No. ML063420372). Therefore, the NRC staff concluded that obtaining the ASME Code required examination volume is impractical, because it would impose a burden upon the licensee, and that the UT examinations that were performed to the maximum extent possible provide reasonable assurance of the structural integrity of the RPV flange threads. 3.5.4 Compensatory Measures The NRC staff noted that FPL's "proposed alternatives," listed in Section 3.4 of this safety evaluation, are not proposals for alternatives pursuant to 10 CFR 50.55a(z) (formerly 10 CFR 50.55a(a)(3)). Periodic system pressure testing of the RPV pressure retaining boundary in accordance with Examination Category B-P of Table IWB-2500-1 of Section XI of the ASME Code is required per 10 CFR 50.55a(g)(4). Conducting UT examinations to the maximum extent possible are discussed in the preceding paragraphs for each of the RPV components addressed
-8 -in the licensee's February 13, 2015, submittal. Both are regarded as compensatory measures due to the scanning limitations. The Examination Category B-P system pressure test includes VT-2 for evidence of leakage, which provides reasonable assurance of leak tightness. Additionally, the licensee stated that in Turkey Point Unit 4, leakage monitoring is provided by the reactor containment sump inlet flow monitoring system, which has high level and alert status alarms in the control room, and that monitoring is performed at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> in accordance with the plant Technical Specifications. Collectively, the VT-2 examinations for both units, and the leakage monitoring system for Turkey Point Unit 4, provide reasonable assurance of leak tightness, and of leak detection should leakage occur. 3.5.5 Evaluation of Impracticality It is not possible to obtain UT examination of greater than 90-percent of the required examination volume due to interference caused by configuration and/or permanent attachments. Examinations were performed to the maximum extent possible. The UT techniques for each weld or surface were reviewed to determine if additional coverage could be achieved. For the welds or surfaces listed above, it was not possible to remove the obstruction without significant work, increased radiation exposure, and/or damage to the plant; therefore, imposing greater than 90-percent examination would be a burden for FPL. 3.5.6 Structural Integrity or Leak Tightness FPL performed 85-percent UT examination for Examination Category B-A, Item B1 .11, 75-percent UT examination for Examination Category B-A, Item B1 .30, and 84.67-percent UT examination for Examination Category B-G-1, Item B6.40. The accessible areas of the RPV shell weld were examined with personnel, equipment and procedures that were qualified by demonstration in accordance with Supplements 4 and 6 of the 1998 Edition up to and including the 2000 Addenda of the ASME Code,Section XI, Appendix VIII, using the POI protocol. These examinations were performed by the licensee from both sides of the welds, scanning both parallel and perpendicular to the weld to the maximum extent possible. FPL performed VT examination the interior of the reactor vessel, including welded attachments, in accordance with Table IWB-2500-1, Examination Categories B-N-1, B-N-2 and B-N-3. The VT examinations revealed no relevant indications according to the licensee. Based on the UT and VT examinations performed by FPL, the NRC staff has reasonable assurance of structural integrity or leak tightness of the RPV welds. 4.0 CONCLUSION Based on the review of the submittals, the NRC staff concluded that compliance with the ASME Code coverage requirements is impractical for the configurations identified in the subject relief requests, and that compliance with the specified requirements would result in a burden on FPL. The NRC staff also concluded that the examination coverages obtained by the licensee provide reasonable assurance of the structural integrity of the affected components. Therefore, relief
-9 -granted pursuant to 10 CFR 55.a(g)(6)(i) is authorized by law and will not endanger life or property or the common defense and security, and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility. Therefore, the NRC staff grants relief for the examinations of the RPV Circumferential Shell Welds (3-WR-31 and 4-WR-31), RPV Shell-to-Flange Welds (3-WR-18 and 4-WR-18), and RPV Threads in Flange (3-Lig-1 through 58 and 4-Lig-1 through 58) contained in RR No. 15 for the Turkey Point, Units 3 and 4 fourth 10-year ISi interval. The relief is granted for the fourth 10-year ISi interval at Turkey Point Unit 3, which began February 22, 2004, and ended February 21, 2014, and for the fourth 10-year ISi interval at Turkey Point Unit 4, which began April 15, 2004, and ended April 14, 2014. All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject request for relief remain applicable, including third-party review by the Authorized Nuclear lnservice Inspector. Principal Contributors: David Dijamco, Gary Stevens, and Carol Nove Date: December 11, 2015