ML101590574

Relief Request Nos. WF3-ISI-007 to WF3-ISI-014 from ASME Code,Section XI Volumetric Examination Requirements - Second 10-Year Interval

ML101590574
Person / Time
Site:	Waterford
Issue date:	06/30/2010
From:	Markley M Plant Licensing Branch IV
To:	Entergy Operations
Kalyanam N, NRR/DORL/LPL4, 415-1480
References
TAC ME1426, TAC ME1427, TAC ME1428, TAC ME1429, TAC ME1430, TAC ME1431, TAC ME1433
Download: ML101590574 (27)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 June 30, 2010 Vice President, Operations Entergy Operations, Inc.

Waterford Steam Electric Station, Unit 3 17265 River Road Killona, LA 70057-3093

SUBJECT:

WATERFORD STEAM ELECTRIC STATION, UNIT 3 - REQUEST FOR RELIEF NOS. WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011, WF3-ISI-012, WF3-ISI-013, AND WF3-ISI-014 FROM ASME CODE, SECTION XI, EXAMINATION REQUIREMENTS FOR SECOND 10-YEAR INSERVICE INSPECTION INTERVAL (TAC NOS. ME1426, ME1427, ME1428, ME1429, ME1430, ME1431, ME1432, AND ME1433)

Dear Sir or Madam:

By letter dated June 1, 2009, supplemented by letters dated November 6, 2009, February 8 and April 29, 2010, Entergy Operations Inc. (Entergy, the licensee), submitted Request for Relief (RR) Nos. WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-010, WF3-ISI-011, WF3-ISI-012, WF3-ISI-013 and WF3-ISI-014 from certain inservice inspection (lSI) requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),

Section XI, at Waterford Steam Electric Station, Unit 3 (Waterford 3). Specifically, the licensee requested relief from certain examination coverage requirements for selected components for the second 1O-year lSI interval, which ended in April 2008.

By letter dated February 8, 2010, Entergy withdrew RR WF3-ISI-014 because it was determined that relief was not needed. Accordingly, the U.S. Nuclear Regulatory Commission (NRC) staff considers the request withdrawn and has closed NRC Task Assignment Control (TAC)

No. ME1433. The letter dated April 29, 2010, was a resubmittal of a letter dated April 8, 2010, which had a page numbering discrepancy between Attachments 1 and 2. The letter dated April 29, 2010, in addition to correcting the discrepancy, also withdrew the relief requests for the Examination Category B-J, Item number B9.21 welds, contained in RR WF3-ISI-010.

The NRC staff has completed its review as documented in the enclosed Safety Evaluation. For certain stainless steel welds contained in RRs WF3-ISI-01 0 and WF3-ISI-013, the licensee employed only shear wave techniques from a single accessible side. In order to ensure that the volumetric examination coverage is maximized, it is recommended that the licensee apply both shear and longitudinal wave techniques on the subject welds during its next scheduled inspections for the components contained in RRs WF3-ISI-01 0 and WF3-ISI-013. While the staff did not include conditions on the approval of RRs WF3-ISI-01 0 and WF3-ISI-013, the licensee is recommended to contact the staff if further discussions are needed. Based on a review of the licensee's submittals, the NRC staff determined that compliance with the ASME Code-required examination coverage is impractical and that the achieved coverage provides reasonable assurance of structural integrity of the selected components. Therefore, pursuant to paragraph 50.55a(g)(6)(i) of Title 10 of the Code of Federal Regulations (10 CFR), relief is

-2 granted for the second 10-year lSI interval for RRs WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011, WF3-ISI-012, and WF3-ISI-013. The NRC staff concludes that granting relief pursuant to 10 CFR 50.55a(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 given due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.

All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject requests for relief remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.

If you have any questions, please contact Kaly N. Kalyanam, Project Manager for Waterford 3, at (301) 415-1480 or bye-mail at kaly.kalyanam@nrc.gov.

Sincerely, Michael T. Markley, Chief Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-382

Enclosure:

As stated 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 SECOND 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM RELIEF REQUESTS NOS. WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011, WF3-ISI-012, WF3-ISI-013, AND WF3-ISI-014 ENTERGY OPERATIONS, INC.

WATERFORD STEAM ELECTRIC STATION, UNIT 3 DOCKET NO. 50-382

1.0 INTRODUCTION

By letter dated June 1, 2009 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML091540088), and supplemented by letters dated November 6, 2009, February 8 and April 29, 2010 (ADAMS Accession Nos. ML093160319, ML100470047, and ML101230324, respectively), Entergy Operations Inc. (Entergy, the licensee), pursuant to paragraph 50.55a(g)(6)(i) of Title 10 of the Code of Federal Regulations (10 CFR), requested relief from the inservice inspection (lSI) requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, pertaining to volumetric, surface, and visual examinations at Waterford Steam Electric Station, Unit 3 (Waterford 3) for selected components. Relief Request (RR) Nos. WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-010, WF3-ISI-011, WF3-ISI-012, WF3-ISI-013, and WF3-ISI-014 are for the second 10-year lSI interval. By letter dated February 8, 2010, Entergy withdrew RR WF3-ISI-014 because it was determined that relief was not needed. The letter dated April 29, 2010, was a resubmittal of a letter dated April 8, 2010, which had a page numbering discrepancy between Attachments 1 and 2. Because of the discrepancy, the letter dated April 8, 2010, was not docketed in ADAMS. The letter dated April 29, 2010, in addition to correcting the discrepancy, also withdrew the relief requests for the Examination Category B-J, Item number B9.21 welds, contained in RR WF3-ISI-01 O.

The U.S. Nuclear Regulatory Commission (NRC) staff, with technical assistance from its contractor, the Pacific Northwest National Laboratory (PNNL), has reviewed and evaluated the information provided by Entergy and adopts the evaluations and recommendations for granting relief contained in PNNL's Technical Letter Report (TLR) dated June 1, 2010 (ADAMS Accession No. ML101520318, non-publicly available), which has been incorporated into this safety evaluation (SE). The Attachment to this SE lists each relief request and the status of approval.

Enclosure

-2

2.0 REGULATORY EVALUATION

Inservice inspection of the ASME Code Class 1, 2, and 3 components is to be performed in accordance with Section XI of the ASME Code, and applicable addenda, as required by 10 CFR 50.55a(g), except where specific relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). The regulation at 10 CFR 50.55a(a)(3) states that alternatives to the requirements of paragraph (g) may be used, when authorized by the NRC, if the licensee demonstrates that (i) the proposed alternatives would 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.

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 pressure tests conducted during the first 1O-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code, which was incorporated by reference in 10 CFR 50.55a(b) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein.

The ASME Code of record for Waterford 3 is the second 1O-year interval lSI program, which ended in April 2008, is the 1992 Edition with 1993 Addenda of the ASME Code,Section XI.

3.0 TECHNICAL EVALUATION

The information provided by Entergy in support of the requests for relief from ASME Code requirements has been evaluated and the bases for disposition are documented below. For clarity, the licensee's requests have been evaluated in several parts according to the ASME Code Examination Category.

3.1 Request for Relief WF3-ISI-007, ASME Code,Section XI, Examination Category B-A.

Items B1.22 and B1.40, Pressure Retaining Welds in Reactor Vessel (TAC No. ME1426) 3.1.1 ASME Code Requirement ASME Code,Section XI, Examination Category B-A, Item B1.22 requires essentially 100 percent volumetric examination, as defined by Figure IWB-2500-3, of the accessible length of reactor pressure vessel (RPV) meridional head welds. Item B1.40 requires essentially 100 percent volumetric and surface examination of the length of RPV head-to-flange welds, as defined by Figure IWB-2500-5. "Essentially 100 percent," as clarified by ASME Code Case N-460, "Alternative Examination Coverage for Class 1 and Class 2 Welds," is 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 1.147, Revision 15 (RG 1.147, Revision 15), "Inservice Inspection Code Case Acceptability."

-3 3.1.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required vOlumetric examination for the Class 1 RPV welds shown in Table 3.1.1.

Table 3.1.1 - ASME Code,Section XI, Examination Category B-A ASME Code Weld ASM E Coverage Item Identifier Weld Type Obtained B1.22 02-002 RPV Head Peel Segment-ta-Peel 18%

Segment at 90° B1.22 02-003 RPV Head Peel Segment-ta-Peel 18%

Segment at 0° B1.40 02-001 RPV Head-ta-Flange 64%

3.1.3 Licensee's Basis for Relief Request (as stated by the licensee):

During ultrasonic [(UT)] examination of the Pressure Retaining Reactor Vessel Welds listed in [Table 3.1.1] of this relief request, 100% coverage of the required examination volume could not be obtained.

Radiography [(RT)] is not practical on these types of weld configurations, which prevents placement of the film and exposure source.

3.1.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.1.5 NRC Staff Evaluation The ASME Code requires essentially 100 percent vOlumetric and surface examination, as applicable, of the accessible length of the RPV meridional head welds and head-to-f1ange welds. However, for the subject welds at Waterford 3, complete examinations are restricted by their design geometry and the proximity of surrounding appurtenances. The RPV would require design modifications and removal of adjacent components to increase the amount of weld volume that can be inspected. Imposing this requirement would place a burden on the licensee; therefore, the ASME Code-required 100 percent volumetric examinations are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittals, the Waterford 3 RPV closure head design includes a shroud surrounding the control rod drive housings and integrally-welded shroud support lugs that restricts access and transducer movement during scanning, and limits volumetric coverage for the meridional head welds to the lower 4 inches of each 22-inch weld length. The licensee obtained 18 percent volumetric coverage of the ASME Code-required inspection volumes for RPV Meridional Head Welds

- 4 02-002 and 02-003. Increasing volumetric coverage for these Welds02-002 and 02-003 would require removing the shroud. The integral support lugs would, however, continue to limit the examinations. The weld examinations for ASME Code,Section XI, Item 81.22 were completed prior to the implementation of inspection techniques qualified under ASME Code,Section XI, Appendix VIII. Therefore, these examinations were conducted using ASME Code-required technical guidance at the time of the examinations. For RPV Closure Head-to-Flange Weld 02-001, the licensee obtained 64 percent vOlumetric coverage due to close proximity of the shroud supports and the flange configuration, which provides only limited access from the flange side of the weld. Manual UT examinations were conducted from the exterior surface of the RPV head with O-degree longitudinal, and 45- and 60-degree shear wave techniques being applied. For ASME Code,Section XI, Item 81.40, the examination was performed to the ASME Code-required technical guidance at the time of the examination. Full coverage was achieved during the magnetic particle surface examination for Weld 02-001. No recordable indications were observed during any of the examinations.

The licensee has shown that it is impractical to meet the ASME Code-required 100 percent volumetric examination coverage for the subject welds due to their design and proximity of adjacent components. However, based on the volumetric and surface coverage obtained, it is reasonable to conclude that if significant service-induced degradation had occurred, evidence of it would have been detected by the examinations that were performed. The NRC staff concluded that the examinations were performed, to the extent practical, on the sUbject RPV welds, and provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.2 Request for Relief WF3-ISI-008, ASME Code,Section XI, Examination Category 8-D, Items 83.110. 83.120. and 83.130. Full Penetration Welded Nozzles in Vessels (TAC No. ME1427) 3.2.1 ASME Code Requirement ASME Code,Section XI, Examination Category 8-D, Items 83.110, 83.120, and 83.130 require 100 percent volumetric examination, as defined by ASME Code, Figures IW8-2500-7(a) through (d), as applicable, of Class 1 pressurizer nozzle-to-vessel welds, nozzle inside radius sections, and steam generator (SG) (primary side) nozzle-to-vessel welds, respectively. ASME Code Case N-460, as an alternative approved for use by the NRC in RG 1.147, Revision 15, states that a reduction in examination coverage due to part geometry or interference for any Class 1 and 2 weld is acceptable provided that the reduction is less than 10 percent (i.e., greater than 90 percent examination coverage is obtained).

-5 3.2.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric examination of the subject nozzle-to-vessel welds and nozzle inside radius sections shown in Table 3.2.1 below:

Table 3.2.1- ASME Code,Section XI, Examination Category B-D ASME ASME Code Weld Coverage Item Identifier Weld Type Obtained 83.110 05-009 Pressurizer Surge Nozzle-to-Head Weld 64%

83.110 05-010 Pressurizer Spray Nozzle-to-Head Weld 74.8%

83.110 05-011 Pressurizer Safety Nozzle-to-Head Weld 65.9%

83.110 05-012 Pressurizer Safety Nozzle-to-Head Weld 65.9%

83.110 05-013 Pressurizer Safety Nozzle-to-Head Weld 65.9%

83.120 05-014 Pressurizer Surge Nozzle Inner Radius 29.4%

83.120 05-015 Pressurizer Spray Nozzle Inner Radius 60.4%

83.120 05-016 Pressurizer Safety Nozzle Inner Radius 72%

83.120 05-017 Pressurizer Safety Nozzle Inner Radius 72%

83.120 05-018 Pressurizer Safety Nozzle Inner Radius 72%

83.130 03-010 42" Hot Leg Nozzle-to-SG#1 86.5%

0 83.130 03-011 30" Cold Leg-to-SG#1 at 45 66%

0 83.130 03-012 30" Cold Leg-to-SG#1 at 315 66%

3.2.3 Licensee's Basis for Relief Request (as stated by the licensee)

During ultrasonic examination of the Reactor and Pressurizer Vessel nozzle-to vessel welds listed in [Table 3.2.1] of this relief request, 100% coverage of the required examination volume could not be obtained.

Radiography is not practical on these types of nozzle-to-vessel weld configurations, which prevent placement of the film and exposure source. To perform any additional Code allowable UT examination, modification and/or replacement of the component would be required. The examinations performed on the subject items in addition to the examination of other vessel welds contained in the 151 program would detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.

3.2.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

-6 3.2.5 NRC Staff Evaluation The ASME Code requires 100 percent volumetric examination of full penetration ASME Code Class 1 welded nozzles in the pressurizer and steam generators. However, the design geometry of the subject nozzle welds and nozzle inside radius sections limit UT scans. In order to effectively increase the examination coverage, these components would require design modifications or replacement. This would place a burden on the licensee; therefore, the ASME Code-required 100 percent volumetric examinations are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittals, examination of the subject nozzles and inside radius sections has been performed to the extent practical with the licensee obtaining aggregate volumetric coverage ranging from approximately 29 to 87 percent (see Table 3.2.1 above). The manual UT examinations on these carbon steel nozzle welds were performed from the outside of the pressurizer and SG, and included scans from the vessel shell using O-degree longitudinal and 45-, 60-, and 70-degree shear waves, as applicable. These nozzles are of the "set-in" design which essentially makes the welds concentric rings aligned parallel with the nozzle axes in the through-wall direction of the pressurizer vessel shell. This design geometry limits ASME Code-required UT angle beam examinations to the vessel side due to the curvature of the nozzle-to-vessel blend radii, which cause contact of the UT search unit to be interrupted. In addition, the pressurizer Safety Nozzle-to-Head Welds05-011, 05-012, and 05-013 UT examinations were also limited 13 to 20 inches circumferentially due to the head-to-shell transition area.

UT examinations on SG Welds03-011 and 03-012 were conducted with equipment, procedures, and personnel that were qualified to the process outlined in ASME Code,Section XI, Appendix VIII. The remaining examinations were performed prior to the required implementation of performance-based qualification techniques; therefore, these examinations were conducted in accordance with the applicable requirements of the ASME Code at the time of the examinations. No recordable indications were observed during any of the UT examinations. Although UT scans were primarily limited to the shell side only, recent studies have found that inspections conducted through carbon steel are equally effective whether the ultrasonic waves have only to propagate through the base metal, or have to also propagate through the carbon steel weldment 1 . Therefore, due to the fine-grained carbon steel microstructures, it is expected that the UT techniques employed would have detected structurally significant flaws that may have occurred on either side of the subject welds.

The licensee has shown that examining 100 percent of the ASME Code-reqUired volumes of the subject nozzle-to-vessel welds and inside radius sections is impractical. However, based on the volumetric coverage obtained, it is reasonable to conclude that if significant service-induced degradation had occurred, evidence of it would have been detected by the examinations that were performed. Furthermore, the NRC staff concluded that the examinations performed to the extent practical on the subject welds provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

P. G. Heasler and S. R. Doctor. 1996. Piping Inspection Round Robin, NUREG/CR-5068.

PNNL-10475, U.S. Nuclear Regulatory Commission, Washington, DC.

-7 3.3 Request for Relief WF3-ISI-009, ASME Code,Section XI, Examination Category B-F, Item B5.40, Pressure Retaining Dissimilar Metal Welds in Vessel Nozzles ASME Code Requirement (TAC No. ME1428) 3.3.1 ASME Code Requirement ASME Code,Section XI, Examination Category B-F, Item B5.40 requires 100 percent volumetric and surface examination, as defined by ASME Code, Figure IWB-2500-8, of nominal pipe size (NPS) 4-inch or larger nozzle-to-safe end dissimilar metal butt welds on vessel nozzles. ASME Code Case N-460, as an alternative approved for use by the !\IRC in RG 1.147, Revision 15, states that a reduction in examination coverage due to part geometry or interference for any Class 1 and 2 weld is acceptable provided that the reduction is less than 10 percent (i.e., greater than 90 percent examination coverage is obtained).

3.3.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric examination of ASME Code Class 1 welds shown in Table 3.3.1 below:

Table 3.3.1- ASME Code,Section XI, Examination Category B-F ASME ASME Code Weld Coverage Item Identifier Weld Type Obtained B5.40 26-006 Pressurizer Nozzle to 8" x 6" Reducing Safe 63%

end Weld B5.40 26-001 Pressurizer Safety Nozzle to 8" x 6" Reducing 70%

Safe end Weld 3.3.3 Licensee's Basis for Relief Request (as stated by the licensee)

During ultrasonic examination of the piping welds listed in Table 1 [Table 3.3.1 above] of this relief request, 100% coverage of the required examination volume could not be obtained.

Class 1 piping and components are often designed with welded joints such as nozzle-to-pipe, pipe-to-valve and pipe-to-pump which can physically obstruct a large portion of the required examination volume. For the welds listed in

[Table 3.3.1] (above), the examinations were performed after November 22, 2002, the 10CFR50.55a mandatory implementation date for Appendix VIII of

[ASME Code] Section XI, and code coverage percentages, provided, reflect what is currently allowed by qualified Appendix VIII techniques. Appendix VIII qualified (POI [Performance Demonstration Initiative]) procedures have demonstrated that sound beams may potentially be attenuated and distorted when required to pass through austenitic weld metal. Still, the POI qualified methods employ the best available technology for maximizing examination coverage of these types of welds. For the components listed in this relief request, examination was

-8 extended to the far side of the weld to the extent permitted by geometry as qualified through PDI.

Entergy has used the best available techniques to examine the subject piping welds. To improve upon these examination coverage percentages, modification and/or replacement of the component would be required. Consistent with the ASME [Code] Section XI sampling approach, examination of the subject welds, when combined with examinations that have been performed on other welds within the same Examination Category, is adequate to detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.

3.3.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.3.5 NRC Staff Evaluation The ASME Code requires essentially 100 percent volumetric and surface examinations for ASME Code,Section XI, Examination Category B-F pressure-retaining dissimilar metal welds in vessel nozzles. However, the design geometries of the subject pressurizer nozzle-to-safe end welds limits the UT scans. In order to effectively increase the examination coverage, these components would require design modification, or replacement. This would place a burden on the licensee, thus, 100 percent ASME Code-required UT examinations are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittals, examinations of the subject welds have been performed to the extent practical with the licensee obtaining volumetric coverage of approximately 63 percent and 70 percent for Pressurizer Safety and Spray Nozzles Welds26-006 and 26-001, respectively. The tapering design geometry of the outside diameter safe end for Welds26-001 and 26-006 limits the full ASME Code coverage from the safe-end side of the weld.

The UT examinations on the carbon steel (nozzle) and stainless steel (safe-end) welds conducted by the licensee included 45-degree shear wave and 45- and 60-degree refracted longitudinal waves (L-wave), where accessible. The L-wave technique is believed capable of detecting planar inside diameter (ID) surface-breaking flaws on the far-side of wrought stainless steel welds. Studies 2 ,3 reported in the technical literature recommend the use of both shear and L-waves to obtain the best detection results, with minimum false calls, in austenitic welds.

These weld examinations were completed prior to the implementation of inspection techniques 2

F. V. Ammirato, X. Edelmann, and S. M. Walker. 1987. "Examination of Dissimilar Metal Welds th in BWR [Boiling-Water Reactor] Nozzle-to-Safe End Joints," 8 International Conference on NDE [Non Destructive Examination] in the Nuclear Industry, ASM International.

3 P. Lemaitre, T. D. Koble, and S. R. Doctor. 1995. "PISC III Capability Study on Wrought-to-Wrought Austenitic Steel Welds: Evaluation at the Level of Procedures and Techniques," Effectiveness of Nondestructive Examination Systems and Performance Demonstration, PVP-Volume 317, NDE-Volume 14, American Society of Mechanical Engineers.

-9 qualified under Appendix VIII of the ASME Code,Section XI; therefore, these examinations were conducted using ASME Code-required technical guidance at the time of the examinations.

No recordable indications were observed during any of the UT examinations.

Subsequent to these examinations, Welds26-006 and 26-001 were mitigated using preemptive full structural weld overlays (see the SE for Request for Alternative W3-R&R-006, dated April 21, 2008, ADAMS Accession No. ML0809502731). In its letter dated May 29,2008 (ADAMS Accession 1\10. ML081540250), the licensee documented the UT examinations performed on the pressurizer weld overlays. For Weld 26-006, the UT examination resulted in 100 percent coverage of the weld overlay material and 93 percent coverage of the required volume for the dissimilar metal weld. For Weld 26-001, the UT examination resulted in 100 percent coverage of the weld overlay material and 91.7 percent coverage of the required volume for the dissimilar metal weld.

The licensee has shown that, prior to weld overlay, it was impractical to meet the ASME Code required volumetric examination coverage for the subject piping welds due to the geometric configuration of the welds. Considering the volumetric coverage obtained prior to weld overlay, combined with the UT examination results obtained subsequent to weld overlay, it is reasonable to conclude that if significant service-induced degradation had occurred in the subject welds, evidence of it would have been detected. The NRC staff concluded that the examinations performed to the extent practical on the subject welds, along with the actions taken to mitigate these welds, provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.4 Request for Relief WF3-ISI-01 0, ASME Code,Section XI. Examination Category 8-J, Items 89.11! 89.21, and 89.31! Pressure Retaining Welds in Piping (TAC No. ME1429) 3.4.1 ASME Code Requirement ASME Code,Section XI, Examination Category 8-J, Items 89.11 and 89.31, require essentially 100 percent volumetric and surface examinations, as defined by Figures IW8-2500-8, -9, -10, and -11, as applicable, for circumferential piping and branch connection welds 4-inch NPS, or larger, in diameter. ASME Code, Item 89.21 requires essentially 100 percent surface examination of the length of circumferential welds less than NPS 4-inch, as defined by ASME Code, Figure IW8-2500-8. "Essentially 100 percent," as clarified by ASME Code Case N-460, is 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 RG 1.147, Revision 15.

- 10 3.4.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric examination of the Class 1 piping welds shown in Table 3.4.1 below:

Table 3.4.1 - ASME Code,Section XI, Examination Category B-J ASME ASME Code Weld Weld/Base Coverage Item Identifier Weld Type Material Obtained B9.11 06-006 14" Shutdown Cooling Nozzle-to- Carbon/Alloy 86.5%

Safe End Weld 82/182 to Stainless Steel (SS)

B9.11 07-013 Reactor Coolant System (RCS) 30" Carbon 82.2%

Elbow to 45° Elbow Weld B9.11 08-014 30" Pipe-to-Safe End Weld Carbon/Alloy 71%

82/182 to SS B9.11 09-002 SG Nozzle Ext. Piece to 30" Elbow Carbon 87%

Ext. Piece Weld B9.11 09-005 45° Elbow to 30" Elbow Weld Carbon 85%

B9.11 09-016 30" Elbow-to-Safe End Weld Carbon/Alloy 52.5%

(Reactor Coolant Pump (RCP) 1B 82/182 to SS Inlet)

B9.11 09-017 30" Safe End-to-RCP 1B Weld SS/Cast SS 17.5%

B9.11 10-001 RCP 1B to 30" Safe End Weld SS/Cast SS 18%

B9.11 10-002 Safe End to 30" Pipe Weld (RCP Carbon/Alloy 44.2%

1B Outlet) 82/182 to SS B9.11 13-001 SG#2 30" Nozzle-to-Nozzle Carbon 62.5%

Extension Weld B9.11 17-033 12" Pipe-to-Reducer Weld Stainless 57%

B9.11 19-006 12" Pipe-to-Valve Weld Stainless 50%

B9.11 19-008 Valve End to 12" Pipe Weld Stainless 50%

B9.11 21-066 14" Pipe-to-Valve Weld Stainless 50%

B9.11 22-023 Elbow to 14" Pipe Weld Stainless 88%

B9.11 25-009 4" Pipe to 4" x 4" x 3" Tee Weld Stainless 75%

B9.11 25-015 4" x 4" x 3" Tee to 4" Pipe Weld Stainless 75%

B9.11 25-016 4" Pipe-to-Valve End Weld Stainless 50%

B9.11 25-018 Valve End to 4" Pipe Weld Stainless 50%

B9.11 25-019 4" Pipe-to-Elbow Weld Stainless 75%

B9.11 25-020 Elbow to 4" Pipe Weld Stainless 75%

B9.11 25-022 Tee to 4" Branch Connection Weld Stainless 62%

B9.11 26-002 8" x 6" Reducing Safe-End to 6" Stainless 50%

Elbow Weld

- 11 Table 3.4.1 - ASME Code,Section XI, Examination Category B-J ASME ASME Code Weld Weld/Base Coverage Item Identifier Weld Type Material Obtained 89.11 26-007 8" x 6" Reducing Safe-End to 6" Stainless 52%

Elbow Weld 89.31 08-008 12" Safety Injection Nozzle to 30" Carbon 50%

Pipe Weld Note: In the licensee's response letter dated April 29, 2010, to the latest NRC Request for Additional Information (RAI), Entergy withdrew the request for relief for volumetric examination of the subject ASME Code, Item B9.21 pressure-retaining piping welds since vOlumetric examinations were performed to satisfy Owner Elected Exams, and not the requirements of ASME Code,Section XI. The licensee completed the ASME Code-required surface examinations on the subject welds. The request for relief from the ASME Code requirements was withdrawn for piping welds listed in Table 3.4.2 below:

Table 3.4.2 - ASME Code,Section XI, Examination Category B-J, Item B9.21 Weld Identifier Weld Identifier Weld Identifier 15-006 27-011 28-012 27-002 27-037 28-013 27-004 27-038 28-016 27-005 27-054 28-074 27-006 27-055 28-075 27-007 28-001 28-076 27-008 28-002 28-077 27-009 28-008 28-078 27-010 28-009 3.4.3 Licensee's Basis for Relief Request (as stated by the licensee)

During ultrasonic examination of the piping welds listed in [Table 3.4.1 above],

100% coverage of the required examination volume could not be obtained.

[ASME Code] Class 1 piping and components are often designed with welded joints such as nozzle-to-pipe, pipe-to-valve and pipe-to-pump which can physically obstruct a large portion of the required examination volume. For many of the welds listed in [Table 3.4.1], the examinations were performed after the 10CFR50.55a mandatory implementation date for Appendix VIII of [ASME Code,]

Section XI, and [ASME Code] coverage percentages, provided, reflect what is currently allowed by qualified [ASME Code,Section XI,] Appendix VIII techniques. [ASME Code, Section Xl,] Appendix VIII qualified POI procedures have demonstrated that sound beams may potentially be attenuated and distorted when required to pass through austenitic weld metal. Still, the POI qualified methods employ the best available technology for maximizing

- 12 examination coverage of these types of welds. For all the components listed in this relief request, examination was extended to the far side of the weld to the extent permitted by geometry, but this portion of the examination is not included in the reported coverage for welds examined under PDI and [ASME Code,Section XI,] Appendix VIII rules.

Entergy has used the best available techniques to examine the subject piping welds. To improve upon these examination coverage percentages, modification and/or replacement of the component would be required. Consistent with the ASME [Code,] Section XI sampling approach, examination of the subject welds, when combined with examinations that have been performed on other welds within the same [ASME Code] Examination Category, is adequate to detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.

3.4.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.4.5 NRC Staff Evaluation The ASME Code requires essentially 100 percent volumetric and surface examinations for selected Examination Category B-J pressure-retaining welds in piping. However, complete volumetric examinations are restricted by several factors, including design, valve and branch connection configurations, and adjacent appurtenances. These conditions preclude the licensee from obtaining full volumetric examinations of these welds. To gain access for examination, the welds and adjacent items would require design modifications or component replacement. Imposition of this requirement would create a burden on the licensee; therefore, the ASME Code-required 100 percent volumetric examinations are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittals, examinations of the subject welds have been performed to the extent practical with the licensee obtaining volumetric coverage ranging from approximately 18 to 88 percent (see Table 3.4.1 above). Various scan limitations in the axial and circumferential directions were caused by the surface angles on the varied weld configurations, and interfering adjacent components such as nozzles, pumps, and permanent support structures.

The UT examinations on the carbon and stainless steel welds conducted by the licensee included 45-, 60-, and 70-degree shear wave scan angles. In addition, the licensee performed O-degree longitudinal, and 40-, 45-, 60-, and 70-degree refracted longitudinal wave (L-wave), as applicable, examinations from the accessible side for many of the welds. The L-wave technique is believed capable of detecting planar ID surface-breaking flaws on the far-side of wrought

- 13 stainless steel welds. Studies 4 ,5 reported in the technical literature recommend the use of both shear and L-waves to obtain the best detection results, with minimum false calls, in austenitic welds. Many of the subject pipe weld volumetric examinations were conducted using manual techniques qualified in accordance with performance demonstration requirements listed in ASME Code,Section XI, Appendix VIII. However, for pipe Welds06-006,08-014,09-016,10-002, and 17-033, manual volumetric examinations were performed prior to the required implementation of performance-based qualification techniques; therefore these examinations were conducted in accordance with the applicable requirements of the ASME Code at the time of the examinations. The licensee also completed the ASME Code-required surface examinations (liquid penetrant and magnetic particle) on the subject pipe welds. No recordable indications were observed during any of the ultrasonic and surface examinations.

For the 30" Elbow-to Safe End Weld (RCP 1B Inlet)09-016, and the Safe End to 30" Pipe Weld (RCP 1B Outlet)10-002, 52.5 percent and 44.2 percent coverage was achieved, respectively.

These examinations were performed with the manual UT techniques utilized prior to the required implementation of performance-based qualification techniques; therefore, these examinations were conducted in accordance with the applicable requirements of the ASME Code at the time of the examinations. Since the year 2000, when these examinations were performed, these welds were identified to be included a population of Alloy 82/182 welds that are subject to primary water stress-corrosion cracking. The nuclear power industry, through the Materials Reliability Program (MRP), developed guidance for inspection and evaluation of primary system piping butt welds in "Materials Reliability Program: Primary System Piping Butt Weld Inspection and Evaluation Guideline (MRP-139)," dated July 14, 2005 (non-proprietary version, MRP-139NP, available in ADAMS Accession No. ML052150196), requires licensees to inspect Alloy 82/182 butt welds such as these welds by December 31,2010. The licensee performed the MRP-139 inspections of these two welds in the current interval using phased array ultrasonic techniques. For Weld 09-016, the examination achieved 100 percent coverage of the required axial and 83 percent of the circumferential coverage (excluding the cast stainless steel material as allowed by MRP-139). For Weld 10-002, the examination achieved 100 percent coverage of the required axial and 81 percent of the circumferential coverage (excluding the cast stainless steel material as allowed by MRP-139). No recordable indications were noted in either of these examinations. Though the coverage was limited on one side due to the cast stainless steel reactor coolant pump, the inspections achieved adequate coverage of the susceptible material to conclude that if significant service-induced degradation had occurred in these welds, evidence of it would have been detected.

For the 30" Safe End-to-RCP 1B Weld 09-017 and the RCP 1B to 30" Safe End Weld 10-001, the licensee reported coverage of 17.5 percent and 18 percent, respectively, for these stainless steel welds. The licensee's coverage calculations did not credit axial scans for circumferential flaws. However, in response to questions from the NRC staff during a telephone call with the 4 F. V. Ammirato, X. Edelmann, and S. M. Walker. 1987. "Examination of Dissimilar Metal Welds in BWR Nozzle-to-Safe End Joints," 8 th International Conference on NDE in the Nuclear Industry, ASM InternationaI.

5 P. Lemaitre, T. D. Koble, and S. R. Doctor. 1995. "PISC III Capability Study on Wrought-to-Wrought Austenitic Steel Welds: Evaluation at the Level of Procedures and Techniques," Effectiveness of Nondestructive Examination Systems and Performance Demonstration, PVP-Volume 317, NDE-Volume 14, American Society of Mechanical Engineers.

- 14 licensee on June 2, 2010, the licensee provided the data sheets for the inspections of these welds (ADAMS Accession No. ML101540478), which indicated that, in addition to the circumferential scans that resulted in the coverage reported, full axial scans were completed in two directions. No indications were detected in these scans.

The licensee has shown that it is impractical to meet the ASME Code-required volumetric examination coverage for the subject piping welds due to the geometry configuration of the welds and proximity of other components. Considering the volumetric coverage obtained, along with the surface examinations performed, it is reasonable to conclude that if significant service induced degradation had occurred in the subject welds, evidence of it would have been detected. Furthermore, the NRC staff concluded that the examinations performed to the extent practical on the subject welds provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.5 Request for Relief WF3-ISI-011! ASME Code,Section XI. Examination Category C-A, Items C1.10 and C1.20, Pressure Retaining Welds in Pressure Vessels (TAC No.

ME1430) 3.5.1 ASME Code Requirement ASME Code,Section XI, Examination Category C-A, Items C1.1 0 and C1.20 require essentially 100 percent volumetric examination, as defined by Figure IWC-2500-1, of the length of shell and head circumferential welds in Class 2 pressure vessels. "Essentially 100 percent," as clarified by ASME Code Case N-460, is 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 RG 1.147, Revision 15.

3.5.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric examinations of the Class 2 pressure-retaining welds shown in Table 3.5.1 below.

Table 3.5.1 - ASME Code,Section XI, Examination Category C-A ASME Weld ASME Coverage Code Item Identifier Weld Type Obtained C1.10 04-026 SG Intermediate Shell-to-Conical Shell 56%

Weld C1.20 04-029 SG#2 Top Head Torus-to-Top Head 89%

Dome Weld C1.20 54-074 Shut Down Heat Exchanger Shell-to- 88%

Flange Weld C1.20 54-075 Shut Down Heat Exchanger Shell-to- 85%

Flange Weld

- 15 3.5.3 Licensee's Basis for Relief Request (as stated by the licensee)

Ouring ultrasonic examination of the piping welds listed in [Table 3.5.1] of this relief request, 100% coverage of the required examination volume could not be obtained.

Class 1 piping and components are often designed with welded joints such as nozzle-to-pipe, pipe-to-valve and pipe-to-pump which can physically obstruct a large portion of the required examination volume. For the welds listed in

[Table 3.5.1] (above), the examinations were performed after November 22, 2002, the 10CFR50.55a mandatory implementation date for Appendix VIII of Section XI, and code coverage percentages, provided, reflect what is currently allowed by qualified Appendix VIII techniques. Appendix VIII qualified (POI) procedures have demonstrated that sound beams may potentially be attenuated and distorted when required to pass through austenitic weld metal. Still, the POI qualified methods employ the best available technology for maximizing examination coverage of these types of welds. For the components listed in this relief request, examination was extended to the far side of the weld to the extent permitted by geometry as qualified through POI.

Entergy has used the best available techniques to examine the subject piping welds. To improve upon these examination coverage percentages, modification and/or replacement of the component would be required. Consistent with the ASME Section XI sampling approach, examination of the subject welds, when combined with examinations that have been performed on other welds within the same Examination Category, is adequate to detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.

3.5.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.5.5 NRC Staff Evaluation The ASME Code requires essentially 100 percent volumetric examination of ASME Code Class 2 vessel circumferential head and shell welds. However, for the subject welds on the SG and shut down heat exchanger, complete examinations are restricted by the design configuration and the proximity of adjacent appurtenances. Achieving greater coverage on these welds would require that these SG and heat exchanger welds be redesigned and modified. This would place a burden on the licensee; therefore, the ASME Code examinations are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittal, examinations of the SG and shut down heat exchanger shell and head circumferential welds have been performed to the extent practical with aggregate volumetric coverage ranging from

- 16 approximately 56 to 89 percent of the ASME Code-required volumes. The SG and shut down heat exchanger are fabricated of carbon steel and stainless steel, respectively.

The licensee performed manual UT examinations on SG Welds04-026 and 04-029 from the shell side using O-degree longitudinal, as applicable, and 45- and 60-degree shear waves to achieve limited circumferential and axial coverage along the weld length. Scans from the opposite side of the welds were limited due to the proximity of the welded insulation support ring and the insulation lugs located 3.5 inches from the weld centerline. SG Weld 04-029 was limited further due to the surface angle on the weld configuration. Removal of the insulation support ring would increase dose to personnel and only increase volumetric coverage by approximately 2 percent. Although UT scans were limited to the shell side of the welds only, studies have found that inspections conducted through carbon steel are equally effective whether the UT waves have only to propagate through the base metal, or have to also propagate through the carbon steel weldment. 6 Therefore, it is expected that the UT techniques employed by the licensee would detect structurally significant flaws that might occur on either side of the subject weld due to the fine-grained carbon steel microstructures in these materials.

In addition, a surface examination (liquid penetrant) was performed on Intermediate Shell-to Conical Shell Weld 04-026.

The licensee performed manual UT examinations on the Shut Down Heat Exchanger "B" Shell to-Flange Welds54-074 and 54-075, including scans from the shell side using 70-degree refracted longitudinal (L-wave), and 45- and 60-degree shear waves to achieve limited circumferential and axial coverage along the weld length. UT scans were restricted by two nozzle reinforcement pads welded to the vessel shell at 0 and 180 degrees and the proximity of the flange. The L-wave technique is believed capable of detecting planar ID surface-breaking flaws on the far-side of wrought stainless steel welds. Studies 7,8 reported in the technical literature recommend the use of both shear and L-waves to obtain the best detection results, with minimum false calls, in austenitic welds.

The subject Class 2 pressure-retaining weld volumetric examinations were conducted in accordance with the applicable requirements of the ASME Code at the time of the examinations.

No recordable flaw indications were observed during any of the examinations.

The licensee has shown that it is impractical to meet the ASME Code-required 100 percent volumetric examination coverage for the subject shell and head circumferential welds due to geometry configuration and interference from surrounding components. Based on the vOlumetric and surface coverage obtained, it is reasonable to conclude that if significant service induced degradation had occurred, evidence of it would have been detected by the P. G. Heasler and S. R. Doctor. 1996. Piping Inspection Round Robin, NUREG/CR-5068, PNNL-10475, U.S. Nuclear Regulatory Commission, Washington, DC.

7 F. V. Ammirato, X. Edelmann, and S.M. Walker. 1987. "Examination of Dissimilar Metal Welds in th BWR Nozzle-to-Safe End Joints," 8 International Conference on NDE in the Nuclear Industry, ASM International.

8 P. Lemaitre, T. D. Koble, and S. R. Doctor. 1995. "PISC III Capability Study on Wrought-to-Wrought Austenitic Steel Welds: Evaluation at the Level of Procedures and Techniques," Effectiveness of Nondestructive Examination Systems and Performance Demonstration, PVP-Volume 317, NDE-Volume 14, American Society of Mechanical Engineers.

- 17 examinations that were performed. Furthermore, the NRC staff concluded that the examinations performed to the extent practical on the subject welds provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.6 Request for Relief WF3-ISI-012. ASME Code,Section XI, Examination Category C-B, Item C2.21, Pressure Retaining Nozzle Welds in Vessels (TAC No. ME1431) 3.6.1 ASME Code Requirement ASME Code,Section XI, Examination Category C-B, Item C2.21 requires 100 percent volumetric and surface examination, as defined by ASME Code, Figure IWC-2500-4(a) or (b),

as applicable, of nozzle-to-shell (or head) welds in Class 2 vessels. ASME Code Case N-460, as an alternative approved for use by the NRC in RG 1.147, Revision 15, states that a reduction in examination coverage due to part geometry or interference for any Class 1 and 2 weld is acceptable provided that the reduction is less than 10 percent (i.e., greater than 90 percent examination coverage is obtained).

3.6.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric and surface examination shown in Table 3.6.1 below.

Table 3.6.1 - ASME Code,Section XI, Examination Category CoB ASME Code Weld ASME Coverage Item Identifier Weld Type Obtained C2.21 04-030 SG#2 Main Steam Nozzle to- 86%

Top Head Dome Weld 3.6.3 Licensee's Basis for Relief Request (as stated by the licensee)

During ultrasonic examination of the piping welds listed in [Table 3.6.1],

100 percent coverage of the required examination volume could not be obtained.

[ASME Code] Class 1 piping and components are often designed with welded joints such as nozzle-to-pipe, pipe-to-valve and pipe-to-pump which can physically obstruct a large portion of the required examination volume. For the welds listed in [Table 3.6.1] (above), the examinations were performed after November 22,2002, the 10 CFR 50.55a mandatory implementation date for Appendix VIII of [ASME Code] Section XI, and code coverage percentages, provided, reflect what is currently allowed by qualified [ASME Code]

Appendix VIII techniques. [ASME Code] Appendix VIII qualified (POI) procedures have demonstrated that sound beams may potentially be attenuated and distorted when required to pass through austenitic weld metal. Still, the POI qualified methods employ the best available technology for maximizing examination coverage of these types of welds. For the components listed in this

- 18 relief request, examination was extended to the far side of the weld to the extent permitted by geometry as qualified through POI.

Entergy has used the best available techniques to examine the subject piping welds. To improve upon these examination coverage percentages, modification and/or replacement of the component would be required. Consistent with the ASME [Code] Section XI sampling approach, examination of the subject welds, when combined with examinations that have been performed on other welds within the same [ASME Code] Examination Category, is adequate to detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.

3.6.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.6.5 NRC Staff Evaluation The ASME Code requires 100 percent vOlumetric and surface examination of ASME Code Class 2 nozzle-to-shell (or head) welds. However, for SG Nozzle-to-Top Head Dome Weld 04-030, complete examination is limited due to the nozzle configuration and adjacent appurtenances. In order to achieve greater volumetric coverage, the nozzle and vessel would have to be redesigned and modified. This would place a burden on the licensee; therefore, the ASME Code vOlumetric examination is considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittal, examination of the carbon steel Nozzle-to-Top Head Dome Weld 04-030 was performed to the extent practical, with the licensee obtaining 86 percent of the required examination volume, including O-degree longitudinal, and 45- and 60-degree shear wave scans from the shell side of the weld. The SG is fabricated of carbon steel material with a nominal thickness of 5.5 inches.

The nozzle's "set-in" design essentially makes the weld a concentric ring aligned parallel with the nozzle axis. For this reason, no scans could be performed from the nozzle side of the weld.

In addition, the proximity of welded insulation lugs, located 5.25 inches from the weld centerline, on the shell side interrupted circumferential ultrasonic scanning. The manual UT examinations were performed in accordance with the applicable requirements of the ASME Code at the time of the examinations. No unacceptable indications were noted during the UT examinations.

Although UT scans were primarily limited to the shell side only, recent studies have found that inspections conducted through carbon steel are equally effective whether the UT waves have only to propagate through the base metal, or have to also propagate through the carbon steel weldment9 . Therefore, due to the fine-grained carbon steel microstructures, it is expected that the UT techniques employed would have detected structurally significant flaws that may have occurred on either side of the subject welds.

9 P. G. Heasler and S. R. Doctor. 1996. Piping Inspection Round Robin, NUREG/CR-5068, PNNL-10475, U.S. Nuclear Regulatory Commission, Washington, DC.

- 19 As documented in the licensee's corrective action process, CR-WF3-201 0-0352, the licensee did not perform the ASME Code-required surface examination for Nozzle-to Shell Weld 04-030.

However, no recordable indications were observed in the last surface examination of the subject Weld 04-030. In addition, the 7.5 percent examination population of ASME Code Class 2 nonexempt piping welds in accordance with ASME Code,Section XI for Class 2 systems, was met. The subject weld will not be inspected in the next refueling outage since the respective SG will be replaced at this time. As stated by the licensee, the missed surface examination on Weld 04-030 was an isolated event and not reportable pursuant to 10 CFR 50.73, "Licensee event report system."

The licensee has shown that it is impractical to meet the ASME Code-required 100 percent vOlumetric examination coverage for the subject nozzle-to-shell weld due to the nozzle design configuration. However, based on the vOlumetric coverage obtained, it is reasonable to conclude that if significant service-induced degradation had occurred, evidence of it would be have been detected by the examinations performed. Furthermore, the NRC staff concluded that the examinations performed to the extent practical on the subject welds provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.7 Request for Relief WF3-ISI-013, ASME Code,Section XI, Examination Category C-F-1 ,

Items C5.11 and C5.21, Pressure Retaining Welds in Austenitic Stainless Steel or High Alloy Piping (TAC No. ME 1432) 3.7.1 ASME Code Requirement ASME Code,Section XI, Examination Category C-F-1, Items C5.11 and C5.21, require 100 percent volumetric and surface examinations, as defined by ASME Code, Figure IWC-2500-7, of selected Class 2 austenitic stainless steel or high alloy circumferential piping welds. ASME Code Case N-460, as an alternative approved for use by the NRC in RG 1.147, Revision 15, states that a reduction in examination coverage due to part geometry or interference for any Class 1 and 2 weld is acceptable provided that the reduction is less than 10 percent (Le., greater than 90 percent examination coverage is obtained).

3.7.2 Licensee's ASME Code Relief Request In accordance with 10 CFR 50.55a(g)(6)(i), the licensee requested relief from the ASME Code required volumetric examinations of the circumferential piping welds shown in Table 3.7.1 below:

Table 3.7.1 - ASME Code,Section XI, Examination Category C-F-1 ASME ASME Weld Pipe Size- Coverage Code Item Identifier Weld Type Thickness Obtained C5.11 55-051 8" Pipe-to-Valve Weld 8.0" - 0.719" 45.5%

C5.11 64-001 Valve to 10" Pipe Weld 10.0" - 0.365" 50%

LPSI [low-pressure spray C5.11 56-001 injection] Valve to 10" Pipe 10.0" - 0.365" 50%

Weld

- 20 Table 3.7.1 - ASME Code,Section XI, Examination Category C-F-1 ASME ASME Weld Pipe Size- Coverage Code Item Identifier Weld Type Thickness Obtained C5.11 56-002 LPSI 10" Pipe-to-Tee Weld 10.0" - 0.365" 50%

C5.11 56-003 LPSI Tee to 10" Pipe Weld 10.0" - 0.365" 50%

14" x 8" Reducing Elbow C5.11 61-071 8.0" - 0.80" 50%

to-Flange Weld 10" Valve-to-Stainless Pipe C5.11 55-001 10.0" - 0.365" 50%

Weld C5.11 56-005 Tee to 10" Pipe Weld 10.0" - 0.365" 50%

10" Pipe to 10" x 6" C5.11 54-043 10.0" - 0.325" 50%

Reducer Weld 8" Pipe-to-Cont.

C5.11 56-077 8.0" - 0.80" 50%

Penetration Weld C5.11 52-004 14" Elbow-to-Tee Weld 14.0" -1.14" 50%

C5.21 60-131 4" Pipe-to-Tee 4.0" - 0.438" 79%

C5.21 60-468 3" Elbow-to-Pipe Weld 3.0" - 0.438" 50%

C5.21 60-469 Pipe-to-Penetration Weld 3.0" - 0.44" 50%

3.7.3 Licensee's Basis for Relief Request (as stated by the licensee)

During the 2nd 10-year lSI interval at WF3 [Waterford 3], 10 CFR 50.55a(g)(6)(ii)(C) mandated an implementation schedule for all licensees to begin use of Appendix VIII of the 1995 Edition, with 1996 Addenda of ASME

[Code] Section XI. As a result, the examinations listed in this relief request were performed utilizing procedures written in accordance with the POI Generic UT Procedures and Appendix VIII. With the implementation of [ASME Code]

Appendix VIII, only}'2 Vee path examinations have been allowed to be used in austenitic materials, and angle beams are no longer credited to extend beyond the centerline of austenitic welds for consideration of Code coverage, in accordance with qualified PDI procedures. Additional discussion, as to the examination coverage determination process when using [ASME Code]

Appendix VIII techniques on single-sided austenitic welds, is provided in Section III of this relief request.

3.7.4 Licensee's Proposed Alternative Examination The licensee did not propose any alternative examinations for the subject welds. However, the licensee's examinations were performed to the maximum extent practical.

3.7.5 NRC Staff Evaluation The ASME Code requires 100 percent VOlumetric and surface examination of selected ASME Code,Section XI, Examination Category C-F-1 pressure-retaining circumferential piping welds.

- 21 The volumetric examination must be applied from both sides of the weld to maximize coverage.

However, volumetric examinations are limited by the geometry of the welds, which restricts scanning to one side only. To gain access for examination, the welds would require design modifications. Imposition of this requirement would create a burden on the licensee; therefore, the ASME Code-required 100 percent volumetric examinations from both sides of the welds are considered impractical.

As shown on the sketches and technical descriptions included in the licensee's submittal, examinations of the subject welds have been performed to the extent practical with the licensee obtaining volumetric coverage ranging from approximately 46 to 79 percent. Access for examination of the subject piping welds is limited to the pipe or elbow side only due to the surface angle caused by the elbow-to-tee, valve-to-pipe, pipe-to-reducer, flange-to-reducer, or tee-to-pipe weld configurations (see Table 3.7.1 above). The UT techniques employed for all but one of these stainless steel welds have been qualified through the industry's PDI Program, which meets ASME Code,Section XI, Appendix VIII requirements. However, for Pipe-to-Valve Weld 55-051, manual volumetric examinations were performed in accordance with the applicable requirements of the ASME Code at the time of the examinations.

Depending on the piping wall thickness (see Table 3.7.1 above), the licensee's UT techniques included 45-, 60-, and 70-degree shear waves, and 60- and 70-degree refracted longitudinal waves (L-waves), as applicable, which have been shown to provide enhanced detection on the far-side of austenitic stainless steel welds 10,11. While the licensee has only taken credit for obtaining 50% volumetric coverage for the majority of the subject piping welds, the techniques employed would have provided coverage beyond the near-side of the welds. A review of the typical weld cross-sectional information indicates that limited volumetric coverage on the far side of the welds has been obtained by the licensee. The licensee also completed surface examinations (liquid penetrant) on several of these welds. No recordable indications were noted during the performance of the volumetric and surface examinations.

The licensee has shown that it is impractical to meet the ASME Code-required 100 percent volumetric examination coverage for the subject piping welds due to their geometric configuration. Although the ASME Code-required coverage could not be obtained, the UT techniques employed would have provided full vOlumetric coverage for the near-side of the welds and limited volumetric coverage for the weld fusion zone and base materials on the opposite side of the welds. Based on the aggregate coverage obtained for the subject welds, and considering the licensee's performance of UT techniques used to maximize this coverage, it is reasonable to conclude that if significant service-induced degradation were occurring, evidence of it would have been detected by the volumetric and surface examinations that were performed. Furthermore, the NRC staff concluded that the examinations concluded to the 10 F. V. Ammirato, X. Edelmann, and S. M. Walker. 1987. Examination of Dissimilar Metal Welds in th BWR Nozzle-to-Safe End Joints, 8 International Conference on NDE in the Nuclear Industry, ASM International.

11 P. Lemaitre, T. D. Koble, and S. R. Doctor. 1995. PISC 1/1 Capability Study on Wrought-to-Wrought Austenitic Steel Welds: Evaluation at the Level of Procedures and Techniques, Effectiveness of Nondestructive Examination Systems and Performance Demonstration, PVP-Volume 317, NDE-Volume 14, American Society of Mechanical Engineers.

- 22 extent practical on the subject welds provide reasonable assurance of structural integrity of the subject welds and is, therefore, acceptable.

3.8 Request for Relief WF3-ISI-014, ASME Code,Section XI, Examination Category R-A, Items R1.20, Alternative Piping Classification and Examination Requirements (TAC No.

ME1433)

By letter dated February 8,2010, Entergy withdrew RR WF3-ISI-014 because it was determined that it is not needed. Therefore, there is no further discussion of RR WF3-ISI-014 in this SE.

4.0 CONCLUSION

S For certain stainless steel welds contained in RRs WF3-ISI-01 0 and WF3-ISI-013, the licensee employed only shear wave techniques from a single accessible side. In order to ensure that the volumetric examination coverage is maximized, the NRC staff recommends that the licensee apply both shear and longitudinal wave techniques on the subject welds during its next scheduled inspections for the components contained in RRs WF3-ISI-01 0 and WF3-ISI-013.

While the staff did not include conditions on the approval of RRs WF3-ISI-010 and WF3-ISI-013, the licensee is recommended to contact the staff if further discussions are needed.

The NRC staff has reviewed the licensee's submittal and concludes that ASME Code examination coverage requirements are impractical for the subject welds listed in RRs WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011, WF3-ISI-012, and WF3-ISI-013. The NRC staff further concludes that, based on the volumetric and surface examination coverage obtained on the subject welds, it is reasonable to conclude that if significant service-induced degradation had occurred, evidence of it would have been detected by the examinations that were performed. Based on the above, the staff concludes that the examinations performed to the extent practical provide reasonable assurance of structural integrity of the subject welds.

Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(g)(6)(i), and is in compliance with the requirements of 10 CFR 50.55a with the granting of these reliefs. Therefore, the NRC staff grants relief for the SUbject examinations of the components contained in RRs WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011 , WF3-ISI-012, and WF3-ISI-013 for Waterford 3 for the second 10-year lSI interval which ended in April 2008. The staff has further concluded that granting these RRs to 10 CFR 50.55a(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 given due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.

RR WF3-ISI-014 was withdrawn by the licensee by letter dated February 8,2010. Therefore, the NRC staff did not review RR WF3-ISI-014.

- 23 All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject requests for relief remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.

Principal Contributors: Thomas McLellan Carol Nove Date: June 30, 2010 Attachment

WATERFORD STEAM ELECTRIC STATION, UNIT 3 Second 10-Year lSI Interval TABLE 1

SUMMARY

OF RELIEF REQUESTS Relief TLR Request RR System or Exam. Item Volume or Area to be Required Licensee Proposed Relief Request Number Sec. Component Category No. Examined Method Alternative Disposition WF3-ISI-007 3.1 Pressure Retaining 8-A 81.22 100% of Class 1 RPV Volumetric and Use volumetric and Granted Welds in Reactor 81.40 meridional head, and Surface, as surface (as 10 CFR 50.55a(g)(6)(i)

Vessel head-to-f1ange welds applicable applicable) coverage achieved WF3-ISI-008 3.2 Full Penetration 8-D 83.110 100% of Class 1 Volumetric Use volumetric Granted Welded Nozzles in 83.120 Pressurizer nozzle-to coverage achieved 10 CFR 50.55a(g)(6)(i)

Vessels 83.130 vessel, nozzle inside radius section, and SG nozzle-to-vessel welds WF3-ISI-009 3.3 Pressure Retaining 8-F 85.40 100% of Class 1 Volumetric and Use volumetric Granted Dissimilar Metal Pressurizer, NPS 4-inch Surface coverage achieved 10 CFR 50.55a(g)(6)(i)

Welds in Vessel or larger, nozzle-to-safe Nozzles end butt welds WF3-ISI-010 3.4 Pressure Retaining 8-J 89.11 100% of Class 1 Surface and Use volumetric and Granted Welds in Piping 89.21 circumferential piping, and Volumetric, as surface coverage 10 CFR 50.55a(g)(6)(i) 89.31 branch pipe connection applicable achieved Item 89.21 withdrawn welds by licensee WF3-ISI-011 3.5 Pressure Retaining C-A CUO 100% of Class 2 shell and Volumetric Use volumetric Granted Welds in Pressure C1.20 head circumferential coverage achieved 10 CFR 50.55a(g)(6)(i)

Vessels welds WF3-ISI-012 3.6 Pressure Retaining C-8 C2.21 100% of Class 2 nozzle Volumetric and Use volumetric Granted Nozzle Welds in to-shell welds Surface coverage achieved 10 CFR 50.55a(g)(6)(i)

Vessels WF3-ISI-0 13 3.7 Pressure Retaining C-F-1 C5.11 100% of Class 2 Volumetric and Use volumetric and Granted Welds in Austenitic C5.21 circumferential piping Surface surface (as 10 CFR 50.55a(g)(6)(i)

Stainless Steel or welds applicable) coverage High Alloy Piping achieved Attachment

-2 granted for the second 10-year lSI interval for RRs WF3-ISI-007, WF3-ISI-008, WF3-ISI-009, WF3-ISI-01 0, WF3-ISI-011, WF3-ISI-012, and WF3-ISI-013. The NRC staff concludes that grantillg relief pursuant to 10 CFR 50.55a(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 given due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.

All other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject requests for relief remain applicable, including third-party review by the Authorized Nuclear Inservice Inspector.

If you have any questions, please contact Kaly N. Kalyanam, Project Manager for Waterford 3, at (301) 415-1480 or bye-mail at kaly.kalyanam@nrc.gov.

Sincerely, IRA!

Michael 1. Markley, Chief Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-382

Enclosure:

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PUBLIC RidsNrrLAJBurkhardt Resource LPLIV Reading RidsNrrPMWaterford Resource RidsAcrsAcnw_MailCTR Resource RidsOgcRp Resource Ridsl'JrrDciCpnb Resource RidsRgn4MailCenter Resource RidsNrrDciCvib Resource TMcLellan, NRR/DCI/CVIB RidsNrrDorlDpr Resource Cl'Jove, NRR/DCI/CPNB RidsNrrDorlLpl4 Resource ADAMS Accession No ML101590574 *SE memo concurrence date OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/DCI/CVIB/BC NRR/DCI/CPNB/BC NRR/LPL4/BC NAME NKalyanam JBurkhardt MMitchel/* TLupold* MMarkley DATE 6/11/10 6/11/10 5/28/10 6/4110 6/30/10 OFFICIAL RECORD COpy