2CAN022202, Requests for Relief from American Society of Mechanical Engineers Section XI Volumetric Examination Requirements - Fourth 10-Year Interval, Second and Third Periods
| ML22055B120 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 02/24/2022 |
| From: | Couture P Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2CAN022202 | |
| Download: ML22055B120 (88) | |
Text
10 CFR 50.55a 2CAN022202 February 24, 2022 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Requests for Relief from American Society of Mechanical EngineersSection XI Volumetric Examination Requirements -
Fourth 10-Year Interval, Second and Third Periods Arkansas Nuclear One, Unit 2 NRC Docket No. 50-368 Renewed Facility Operating License No. NPF-6 REFERENCES 1 Entergy Operations, Inc. (Entergy) letter to the U. S. Nuclear Regulatory Commission (NRC), "Request EN-ISI-16-1 : Use of Later Edition/Addenda of ASME Section XI Code for lSI Related Activities,"
(CNRO-2016-00023), (ML16337A368), dated December 1, 2016.
2 NRC letter to Entergy, "Arkansas Nuclear One, Unit 2 and Indian Point Nuclear Generating Station, Unit No. 3 - Relief Request EN-ISl-16-1 Regarding Use of Later Edition and Addenda of the ASME Code (CAC NOS. MF8905 AND MF8906)," (ML17174B144), dated July 12, 2017.
Pursuant to 10 CFR 50.55a(z)(2), Entergy Operations, Inc. (Entergy) requests relief from the requirements of American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section XI pertaining to the limited surface and volumetric examinations at Arkansas Nuclear One, Unit 2 (ANO-2). In several locations, the required coverage cannot be obtained due to interference or geometry. Individual relief requests are provided in the attachments, divided by examination category.
10 CFR 50.55a(g)(5)(iii) requires that the basis for the determination of impracticality be submitted to the NRC for review and approval within 12 months after the expiration of the 120-month inspection interval. These reliefs are for the fourth ANO-2 10-year Inservice Inspection (ISI) interval, second and third periods. The interval started on March 26, 2010, and ended on August 1, 2020. The second period started on March 26, 2013, and ended March 25, 2017. The third period started March 26, 2017 and ended August 1, 2020. The interval was extended to end March 25, 2021.
Entergy Operations, Inc.
1340 Echelon Parkway Jackson, MS 39213 Tel 601-368-5138 Phil Couture Sr. Manager, Fleet Regulatory Assurance
2CAN022202 Page 2 of 2 It should be noted that the 2001 Edition / 2003 Addenda of Section XI of the ASME Code was the Code of Record when the fourth interval commenced. ANO-2 requested (Reference 1) and was approved (Reference 2) to use the 2007 Edition / 2008 Addenda of Section XI of the ASME Code for ISI activities for the remainder of the fourth ANO-2 ISI interval. ISI examinations performed in the 26th and 27th refueling outages, Fall of 2018 and Spring of 2020, were performed to the requirements of the 2007 Edition / 2008 Addenda of Section XI.
All examinations performed prior to that used the 2001 Edition / 2003 Addenda.
There are no new regulatory commitments made in this submittal.
If you have any questions or require additional information, please contact Riley Keele at 479-858-7826.
Respectfully, Phil Couture PC/rwc Attachments:
- 1.
Request for Relief - ANO2-ISI-023
- 2.
Request for Relief - ANO2-ISI-024
- 3.
Request for Relief - ANO2-ISI-025
- 4.
Request for Relief - ANO2-ISI-026
- 5.
Request for Relief - ANO2-ISI-027
- 6.
Request for Relief - ANO2-ISI-028 cc:
NRC Region IV Regional Administrator NRC Senior Resident Inspector - Arkansas Nuclear One NRC Project Manager - Arkansas Nuclear One Philip Couture Digitally signed by Philip Couture Date: 2022.02.24 15:56:07 -06'00'
2CAN022202 Request for Relief ANO2-ISI-023 2CAN022202 Page 1 of 24 REQUEST FOR RELIEF ANO2-ISI-023 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 1
References:
ASME Section XI 2001 Edition with 2003 Addenda, Table IWB-2500-1 ASME Code Case N-460 Examination Category: B-D Item Number(s)
B3.110, B3.130, B3.140, B3.90
==
Description:==
Full Penetration Welded Nozzles in Vessels Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Second (2nd) and Third (3rd) Inspection Periods I.
CODE REQUIREMENTS ASME Section XI, Table IWB-2500-1, Examination Category B-D, Full Penetration Welded Nozzles in Vessels - Inspection Program B:
- 1) Item B3.110 requires a volumetric examination of Pressurizer Nozzle-to-Vessel Weld volume, as depicted in Figures IWB-2500-7(a) through (d), as applicable.
- 2) Item B3.130 requires a volumetric examination of Steam Generators (Primary Side) Nozzle-to-Vessel Weld volume, as depicted in Figures IWB-2500-7(a) through (d), as applicable.
- 3) Item B3.140 requires a volumetric examination of Steam Generators (Primary Side) Nozzle Inside Radius Section volume, as depicted in Figures IWB-2500-7(a) through (d), as applicable.
- 4) Item B3.90 requires a volumetric examination of Reactor Vessel welds as depicted in Figures IWB-2500-7 (a) through (d).
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
2CAN022202 Page 2 of 24 II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(iii), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
III.
BASIS FOR RELIEF During ultrasonic examination of the nozzle-to-vessel welds and inner radii listed in Table 1 below, 100% coverage of the required examination volume could not be obtained.
Examinations were performed utilizing 0, 45 and 60 beam angles in the axial and circumferential directions in accordance with Entergy approved procedures specific to ferritic vessels greater than 2 inches in thickness.
Due to the geometric configuration of the components and the close proximity of other structures which limited scan paths, the use of approved beam angles in the axial and circumferential direction were not able to achieve greater than 90% code required volume.
See Table 1 for additional information.
Radiography is not practical on these types of nozzle-to-vessel weld configurations, which prevent placement of the film and exposure source. To effectively perform any significant additional Code allowable ultrasonic examinations, 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 Inservice Inspection program would detect generic degradation, if it existed, therefore, demonstrating an acceptable level of integrity.
IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined these welds to the extent practical and will continue to perform pressure testing on the subject components as required by the Code.
V.
CONCLUSION 10 CFR 50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines is authorized by law, 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.
2CAN022202 Page 3 of 24 Entergy believes that it is impractical to obtain greater examination coverage on these welds. To effectively obtain significant additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject welds, in addition to the examination of similar welds contained in the program, would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 4 of 24 Table 1 Limited B-D Examinations Component Description Additional Information Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results B3.110 05-009 Pressurizer (PZR) Surge Nozzle-to-Head Circumferential Weld 67.51 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and head are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 1 and 1a) derived from ultrasonic testing (UT) examination performed in 2R23 and report 2-ISI-UT-14-017 on file at ANO.
Manual UT Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, and 60°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable B3.130 03-005 Steam Generator (SG)
A Primary Outlet Nozzle-to-Extension Pipe Circumferential Weld 86.65 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and extension piece are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 2 and 2a) derived from UT examination performed in 2R23 and report 2-ISI-UT-14-013 on file at ANO.
Manual UT Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 35°,45°, 60° and 70°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable B3.130 03-006 SG A Primary Outlet Nozzle-to-Extension Pipe Circumferential Weld 86.65 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and extension piece are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 3 and 3a) derived from UT examination performed in 2R23 and report 2-ISI-UT-14-014 on file at ANO.
Manual UT Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 35°, 45°, 60° and 70°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 5 of 24 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results B3.130 04-005 SG B Primary Outlet Nozzle-to-Extension Pipe Circumferential Weld 88.44 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and extension piece are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 4 and 4a) derived from UT examination performed in 2R24 and reports 2-ISI-UT-15-007 & 010 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, and 60°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable B3.130 04-006 SG B Primary Outlet Nozzle-to-Extension Pipe Circumferential Weld 88.44 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and extension piece are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 5 and 5a) derived from UT examination performed in 2R24 and reports 2-ISI-UT-15-008 & 011 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, and 60°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable B3.130 04-007 Extension Pipe-to-SG B Primary Inlet Nozzle Circumferential Weld 87.21 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and extension piece are carbon steel with stainless steel cladding on the inside surface.
See the attached information (Figure 6 and 6a) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-018 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 35°, 45°, and 60°.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 6 of 24 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results B3.140 04-005IR SG B Primary Outlet Nozzle Inner Radii 89.03 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and head are carbon steel with stainless steel cladding on the inside surface.
Scanning was performed from the vessel side only due to component configuration.
See the attached information (Figure 7 and 7a) derived from UT examination performed in 2R24 and reports 2-ISI-UT-15-001 and 2-ISI-UT-15-002 on file at ANO.
Manual UT Scan path limitation due to the configuration of the component. Four integral attachments, each 4.25 x 3.75 in size, located on the SG lower head, reduced examination.
Wave modality and insonification angles included 25 shear at 90 skew angle; 35 shear at +120 and -120 skew angles; 55 shear at +22 and -22 skew angles and 70 shear at +19 and -19 skew angles.
Search unit frequencies were 2.25 MHz.
None required.
No indications were observed or recorded.
Acceptable B3.140 04-006IR SG B Primary Outlet Nozzle Inner Radii 89.03 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and head are carbon steel with stainless steel cladding on the inside surface.
Scanning was performed from the vessel side only due to component configuration.
See the attached information (Figure 7 and 7a) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-003 and 2-ISI-UT-15-004 on file at ANO Manual UT.
Scan path limitation due to the configuration of the component. Four integral attachments, each 4.25 x 3.75 in size, located on the SG lower head, reduced examination.
Wave modality and insonification angles included 25 shear at 90 skew angle; 35 shear at +120 and -120 skew angles; 55 shear at +22 and -22 skew angles and 70 shear at +19 and -19 skew angles.
None required.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 7 of 24 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results B3.90 01-021 RPV Nozzle to Shell Weld @ 0° Azimuthal 73.83 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and vessel are carbon steel with stainless steel cladding on the inside surface. Scanning was performed remotely from the vessel internally only due to component configuration and access.
See the attached information (Figure 8, 8a and 8b) derived from UT examination performed in 2R26 and report 2-ISI-VE-18-032 and Wesdyne Report WDI-PJF-1320221-FSR-001 on file at ANO.
Automated UT.
Scan path limitation due to the configuration of the component.
Wave modality and insonification angles included 45° shear and 45° Long., Bore Scan angles included 50°,
35°, 5°, 40°, 25° None required.
No indications were observed or recorded.
Acceptable B3.90 01-024 RPV Nozzle to Shell Weld @
180° Azimuthal 73.83 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-7 was limited due to the component configuration. Both the nozzle and vessel are carbon steel with stainless steel cladding on the inside surface. Scanning was performed remotely from the vessel internally only due to component configuration and access.
See the attached information (Figure 8, 8a, and 8b) derived from UT examination performed in 2R26 and report 2-ISI-VE-18-035 and Wesdyne Report WDI-PJF-1320221-FSR-001 on file at ANO.
Automated UT.
Scan path limitation due to the configuration of the component.
Wave modality and insonification angles included 45° shear and 45° Long., Bore Scan angles included 50°,
35°, 5°, 40°, 25° None required.
Two indications were observed and recorded.
Both were evaluated and acceptable per IWB-3512-1 2CAN022202 Page 8 of 24 Figure 1 Scan Plan and Coverage for ISI Component 05-009 Not to Scale 2CAN022202 Page 9 of 24 Figure 1a Location sketch and photo for ISI Component 05-009 Not to Scale 05-009 2CAN022202 Page 10 of 24 Figure 2 Scan Plan and Coverage for ISI Component 03-005 Not to Scale 2CAN022202 Page 11 of 24 Figure 2a Location sketch and photo for ISI Component 03-005 Not to Scale 2CAN022202 Page 12 of 24 Figure 3 Scan Plan and Coverage for ISI Component 03-006 Not to Scale 2CAN022202 Page 13 of 24 Figure 3a Location sketch and photo for ISI Component 03-006 Not to Scale 2CAN022202 Page 14 of 24 Figure 4 Scan Plan and Coverage for ISI Component 04-005 Not to Scale 2CAN022202 Page 15 of 24 Figure 4a Location sketch and photo for ISI Component 04-005 Not to Scale 2CAN022202 Page 16 of 24 Figure 5 Scan Plan and Coverage for ISI Component 04-006 Not to Scale 2CAN022202 Page 17 of 24 Figure 5a Location sketch and photo for ISI Component 04-006 Not to Scale 2CAN022202 Page 18 of 24 Figure 6 Scan Plan and Coverage for ISI Component 04-007 Not to Scale 2CAN022202 Page 19 of 24 Figure 6a Location sketch and photo for ISI Component 04-007 Not to Scale 2CAN022202 Page 20 of 24 Figure 7 Scan Plan and Coverage for ISI Components 04-005IR and 04-006IR Not to Scale 120 118 116 114 112 110 108 4 6 8 10 12 14 16 R
Z 70/19bd 120 118 116 114 112 110 108 4 6 8 10 12 14 16 R
Z 55/22bd 120 118 116 114 112 110 108 4 6 8 10 12 14 16 R
Z 25/90bd 120 118 116 114 112 110 108 4 6 8 10 12 14 16 R
Z 35/120bd 2CAN022202 Page 21 of 24 Figure 7a Location sketch and photo for ISI Components Not to Scale 2CAN022202 Page 22 of 24 Figure 8 Location Sketch for ISI Components01-021 and 01-024 Not to Scale 2CAN022202 Page 23 of 24 Figure 8a Nozzle Configuration and Exam Volume Sketch for ISI Components01-021 and 01-024 Not to Scale 2CAN022202 Page 24 of 24 Figure 8b Nozzle Exam Coverage Sketch for ISI Components01-021 and 01-024 Not to Scale
2CAN022202 Request for Relief ANO2-ISI-024 2CAN022202 Page 1 of 11 REQUEST FOR RELIEF ANO2-ISI-024 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 1
References:
ASME Section XI 2001 Edition with 2003 Addenda, Table IWC-2500-1 ASME Code Case N-460 Examination Category: B-O Item Number(s)
B14.10
==
Description:==
Pressure Retaining Nozzle Welds in Control Element Drive Mechanism (CEDM) Housing Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Second (3rd) Inspection Period I.
CODE REQUIREMENTS ASME Section XI, Table IWB-2500-1, Examination Category B-O, Pressure Retaining Nozzle Welds in Vessels:
- 1)
Item B14.10 requires a surface examination or a volumetric examination of the Welds in the Control Rod Housings, as depicted in Figure IWB-2500-18 of 10%
of the peripheral CRD housing welds.
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(i), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
III.
BASIS FOR RELIEF In 2008, a cooling shroud (Figure 2) was designed and installed around the ANO-2 Reactor Vessel CEDMs (Figure 3). The modification impacted availability to the peripheral CEDM welds because the welds cannot be accessed now without 2CAN022202 Page 2 of 11 repositioning or removing the cooling shroud assembly. The cooling assembly was designed to be lifted a total of 40 inches. In order to gain access to the entire CEDM housing, a significant design modification would have to be performed. The CEDM instrumentation is highly sensitive and the likelihood of damaging the equipment is high.
Dose estimates to remove the cooling assembly, perform examinations and replace the cooling assembly is 6,690 RWP hours and 8.172 rem.
Per ASME Section XI, a 100% surface examination of 10% of the peripheral CEDM housing welds must be examined each inspection interval. This results in four welds on three CEDMs must be examined each interval. ANO-2 chose to inspect the welds on peripheral CEDM 69, 80 and 81 to satisfy the 10% examination population. CEDM 57, 69 and 80 provided the best opportunity to perform code required examinations. Each CEDM contains four pressure boundary welds labeled on Figure 1 below as W, X, Y, and Z. The top Z weld on CEDM 69, 80 and 81 (shown on ISI-202 drawing) was satisfactorily examined during 2R26 (Fall 2018). Attempts were made in 2R26 to examine the W, X, and Y welds but were unsuccessful. Corrective actions were generated to develop an action plan to complete the ASME Section XI required examinations on the ANO-2 CEDM housing welds in 2R27 (Spring 2020).
During the attempted remote surface examination of the ANO-2 CEDM pressure housing welds X and Y, 0% coverage of the required examination area was obtained due to limited access. The failed attempt was entered into the Entergy Corrective Action Program (CAP). It was noted that a remote VT-1 examination was successfully performed per the plan put in place for the previously selected X and Y welds.
Due to the geometric configuration of the components and the close tolerances of the cooling shroud assembly, coverage could not be obtained to meet the code required inspection area. The W and Z welds were examined 100% using a qualified surface examination method (Penetrant Test [PT]). A qualified surface (PT) examination was attempted, but due to the distance from the top of the Reactor Vessel Closure Head (RVCH) structure (Figure 4, 5 and 6) and the tight tolerances of the cooling shroud assembly, 0% coverage could be claimed for the X and Y welds yielding a total of 50% coverage being obtained for Category B-O. See Table 1 below for additional information.
An Eddy Current surface exam could not be performed because of limited access.
Due to the configuration and limited space, a volumetric examination could not be performed from the outside diameter of the CEDM housing at the X and Y weld locations.
A VT-2 examination in accordance with IWB-2500 was performed of the RVCH area to look for evidence of leakage. There were no indications or relevant conditions identified during the performance of the VT-2.
A Visual Examination (VE) in accordance with ASME Code Case N-729 and a VT-2 in accordance with ASME Section XI Table IWB-2500 is performed every refueling outage looking for evidence of leakage from the RVCH including the CEDM housings. No evidence of leakage has been observed.
2CAN022202 Page 3 of 11 IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined the subject items to the extent practical and will continue to perform pressure testing on the subject areas as required by the Code.
V.
CONCLUSION 10 CFR50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines 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.
Entergy believes that it is impractical to obtain greater examination coverage on these areas. To obtain additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject areas, in addition to the examination of similar welds contained in the program would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Therefore, Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 4 of 11 Table 1 Limited B-O Examinations Component Description Additional Information Item Number Comp. ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Exam Plan Exam Method and Limitations Search Units Surface Examination Exam Results B14.10 CEDM-057 CEDM Motor Housing Upper Weld 50 Examination of the required surface as depicted in Figure IWB-2500-18 was limited due to the component configuration and limited access to two (X, Y) of the four welds (W, X, Y, Z) required to be examined on this CEDM.
See the attached information (Figures 1-6) derived from drawing ISI-202 on file at ANO and photos gathered from 2R26 and 2R27. Reference reports 2-ISI-PT-18-006, 2-ISI-PT-20-003, 2-ISI-VT-20-119, 2-ISI-VT-20-122 Surface Exam, Liquid Penetrant Limitation due to the inaccessibility of the X and Y welds.
N/A Performed successful ASME XI (PT) examinations on Z weld on CEDM 81 in 2R26, on W weld on CEDM 57 in 2R27.
Performed remote VT-1 exam on X and Y welds on CEDM 57 due to limitation in 2R27.
No indications were observed or recorded.
Acceptable B14.10 CEDM-069 CEDM Motor Housing Upper Weld 50 Examination of the required surface as depicted in Figure IWB-2500-18 was limited due to the component configuration and limited access to two (X, Y) of the four welds (W, X, Y, Z) required to be examined on this CEDM.
See the attached information (Figures 1-6) derived from drawing ISI-202 on file at ANO and photos gathered from 2R26 and 2R27. Reference reports 2-ISI-PT-18-004, 2-ISI-PT-20-005, 2-ISI-VT-20-120, 2-ISI-VT-20-123 Surface Exam, Liquid Penetrant Limitation due to the inaccessibility of the X and Y welds.
N/A Performed successful ASME XI (PT) examinations on Z weld in 2R26, on W weld in 2R27. Performed remote VT-1 exam on X and Y welds due to limitation in 2R27.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 5 of 11 Item Number Comp. ID Item Description Estimated Coverage of Code Required Volume Examination Summary Exam Plan Exam Method and Limitations Search Units Surface Examination Exam Results B14.10 CEDM-080 CEDM Motor Housing Upper Weld 50 Examination of the required surface as depicted in Figure IWB-2500-18 was limited due to the component configuration and limited access to two (X, Y) of the four welds (W, X, Y, Z) required to be examined on this CEDM.
See the attached information (Figures 1-6) derived from drawing ISI-202 on file at ANO and photos gathered from 2R26 and 2R27. Reference reports 2-ISI-PT-18-005, 2-ISI-PT-20-004, 2-ISI-VT-20-121, 2-ISI-VT-20-124 Surface Exam, Liquid Penetrant Limitation due to the inaccessibility of the X and Y welds.
N/A Performed successful ASME XI (PT) examinations on Z weld in 2R26, on W weld in 2R27. Performed remote VT-1 exam on X and Y welds due to limitation in 2R27.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 6 of 11 Figure 1 Location for Component CEDM (Typical)
Not to Scale ASME Section XI (PT) examination performed on Z weld successfully in 2R26 with no limitations and acceptable results.
ASME Section XI (PT) examination performed on W weld successfully in 2R27 with no limitations and acceptable results.
ASME Section XI (PT) examination on X and Y welds were unsuccessful in 2R26 and 2R27.
Performed a remote visual (VT-1) on both welds with no limitations and acceptable results during 2R27.
2CAN022202 Page 7 of 11 Figure 2 Cooling Shroud Assembly Not to Scale 2CAN022202 Page 8 of 11 Figure 3 Cooling Shroud Assembly photo taken during installation in 2008 2CAN022202 Page 9 of 11 Figure 4 Reactor Vessel Closure Head (RVCH) Support Structure photo taken during 2R26 2CAN022202 Page 10 of 11 Figure 5 Top of RVCH Support Structure photo taken during 2R26 (Coil Stacks removed from CEDM 69 and 81) 2CAN022202 Page 11 of 11 Figure 6 Lower access panel removed from RVCH Support Structure photo taken during 2R26 (Cooling Shroud Assembly surrounding Lower CEDM section)
2CAN022202 Request for Relief ANO2-ISI-025 2CAN022202 Page 1 of 5 REQUEST FOR RELIEF ANO2-ISI-025 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 2
References:
ASME Section XI 2001 Edition with 2003 Addenda, Table IWC-2500-1 ASME Code Case N-460 Examination Category: C-A Item Number(s)
C1.10
==
Description:==
Pressure Retaining Nozzle Welds in Vessels Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Third (3rd) Inspection Period I.
CODE REQUIREMENTS ASME Section XI, Table IWC-2500-1, Examination Category C-B, Pressure Retaining Nozzle Welds in Vessels - Inspection Program B:
- 1)
Item C1.10 requires a volumetric examination of the Shell Circumferential Welds, as depicted in Figure IWC-2500-1.
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(i), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
III.
BASIS FOR RELIEF During ultrasonic examination of the Letdown Heat Exchanger Flange to Channel Circumferential Weld and the Shutdown Cooling Heat Exchanger Flange to Channel Cylinder and Channel Cylinder to Tubesheet Welds listed in Table 1 below, 100% coverage of the required examination volumes could not be obtained.
2CAN022202 Page 2 of 5 Due to the geometric configuration of the components and the close proximity of other structures which limited scan paths, the use of approved beam angles in the axial and circumferential direction were not able to achieve greater than 90% code required volume.
See Table 1 below for additional information.
Radiography is not practical on these types of nozzle-to-vessel weld configurations, which prevent placement of the film and exposure source. To effectively perform any significant additional Code allowable ultrasonic examinations, 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 Inservice Inspection (ISI) program would detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.
IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined the subject items to the extent practical and will continue to perform pressure testing on the subject areas as required by the Code.
V.
CONCLUSION 10 CFR 50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines 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.
Entergy believes that it is impractical to obtain greater examination coverage on these areas. To obtain additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject areas, in addition to the examination of similar welds contained in the program would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Therefore, Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 3 of 5 Table 1 Limited C-A Examinations Component Description Additional Information Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results C1.10 49-001 Channel Flange to Channel Shell Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWC-2500-1 was limited due to the component configuration and proximity of the channel head flange. Both the flange and channel shell are stainless steel.
See the attached information (Figures 1 and 1a) derived from UT examination performed in 2R27 and report 2-ISI-UT-20-002 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 45°, 60°, 60L°,
and 70°.
Search unit frequencies were 2.0 MHz for 60°L and 2.25 MHz for all shear angles.
None required.
No indications were observed or recorded.
Acceptable 2CAN022202 Page 4 of 5 Figure 1 Scan Plan and Coverage for ISI Component 49-001 Not to Scale 2CAN022202 Page 5 of 5 Figure 1a Location sketch and photo for ISI Component 49-001 Not to Scale Photo taken prior to installation in 2R25
2CAN022202 Request for Relief ANO2-ISI-026 2CAN022202 Page 1 of 8 REQUEST FOR RELIEF ANO2-ISI-026 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 2
References:
ASME Section XI 2001 Edition with 2003 Addenda, Table IWC-2500-1 ASME Code Case N-460 Examination Category: C-B Item Number(s)
C2.21
==
Description:==
Pressure Retaining Nozzle Welds in Vessels Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Second (2nd) and Third (3rd) Inspection Period I.
CODE REQUIREMENTS ASME Section XI, Table IWC-2500-1, Examination Category C-B, Pressure Retaining Nozzle Welds in Vessels - Inspection Program B:
- 1)
Item C2.21 requires a surface and a volumetric examination of the Nozzle-to-Shell (or Head) Weld, as depicted in Figure IWC-2500-4 (a) or (b).
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(i), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
III.
BASIS FOR RELIEF During ultrasonic examination of the Feedwater Nozzle-to-Shell Weld listed in Table 1 below, 100% coverage of the required examination volumes could not be obtained due to the proximity of one of the steam generator insulation brackets which is located around the circumference of the vessel and directly below the Feedwater nozzles. Scan paths from below the nozzle were impeded.
2CAN022202 Page 2 of 8 There are several insulation bracket rings located around the circumference of the steam generator. These brackets facilitate supporting the many insulation panels surrounding the circumference of the steam generator. Removal of the subject bracket requires removal of all insulation panels directly supported by that ring as well as removal or engineered rigging of all insulation rings and panels above the removed ring. The insulation rings are not bolted directly to the steam generator shell; therefore, each lower elevation ring helps support the above rings and insulation panels.
Radiography is not practical on these types of nozzle-to-vessel weld configurations, which prevent placement of the film and exposure source. To effectively perform any significant additional Code allowable ultrasonic examinations, modification and/or removal are replacement of the insulation ring would be required. The examinations performed on the subject items in addition to the examination of other vessel welds contained in the Inservice Inspection program would detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.
IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined the subject items to the extent practical and will continue to perform pressure testing on the subject areas as required by the Code.
V.
CONCLUSION 10 CFR 50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines 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.
Entergy believes that it is impractical to obtain greater examination coverage on these areas. To obtain additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject areas, in addition to the examination of similar welds contained in the program would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Therefore, Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 3 of 8 Table 1 Limited C-B Examinations Component Description Additional Information Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results C2.21 04-002 Steam Generator B Feedwater Nozzle to Shell Weld 69.57 This is a single sided examination but scanned to the extent practical from Nozzle side of weld to maximize coverage. Examination of the required volume as depicted in Figure IWC-2500-4 was limited due to the shell to nozzle blend area and the proximity of an insulation bracket ring below the nozzle. Both the nozzle and vessel shell are carbon steel.
See the attached information (Figures 1 and 1a) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-017 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component and proximity of insulation bracket ring.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, and 60°.
Search unit frequencies were 2.25 MHz.
A Surface examination was performed and documented on 2-ISI-MT-15-002 on file at ANO.
100% of the required surface was examined No indications were observed or recorded.
Acceptable C2.21 48-013 2E35A Shutdown Cooling Heat Exchanger Channel Inlet Nozzle 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWC-2500-4 was limited due to the component configuration. Both the nozzle and Channel are stainless steel.
See the attached information (Figures 2 and 2a) derived from UT examination performed in 2R27 and report 2-ISI-UT-20-004 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, 60°, 60°L, and 70°.
Search unit frequencies were 2.0 MHz for 60°L and 2.25 MHz for all shear angles.
A Surface examination was performed and documented on 2-ISI-PT-20-013 on file at ANO.
100% of the required surface was examined No indications were observed or recorded.
Acceptable 2CAN022202 Page 4 of 8 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination C2.21 48-014 2E35A Shutdown Cooling Heat Exchanger Channel Outlet Nozzle 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWC-2500-4 was limited due to the component configuration. Both the nozzle and Channel are stainless steel.
See the attached information (Figures 2 and 2a) derived from UT examination performed in 2R27 and report 2-ISI-UT-20-005 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 0°, 45°, 60°, 60°L, and 70°.
Search unit frequencies were 2.0 MHz for 60°L and 2.25 MHz for all shear angles.
A Surface examination was performed and documented on 2-ISI-PT-20-006 on file at ANO.
100% of the required surface was examined No indications were observed or recorded.
Acceptable 2CAN022202 Page 5 of 8 Figure 1 Scan Plan and Coverage for ISI Component 04-002 Not to Scale Insulation Bracket Obstruction Not to Scale Top Dead Center 04-002 Weld 41 Dia.,
128.8 Circumference @ CL of weld INSULATION BRACKET 87.5%
60° 45° 45° NOZZLE 60° 45° 60° SHELL C L 100%
50%
FW Nozzle Limited at BDC:
45° - approx. 26.4 = 0% cov.
60° - approx. 32.1 = 0% cov 87.5%
60° 45° 2CAN022202 Page 6 of 8 Figure 1a Location sketch and photo for ISI Component 04-002 Not to Scale 2CAN022202 Page 7 of 8 Figure 2 Scan Plan and Coverage for ISI Components48-013 and 48-014 Not to Scale 2CAN022202 Page 8 of 8 Figure 2a Location sketch and photo for ISI Components48-013 and 48-014 Not to Scale
2CAN022202 Request for Relief ANO2-ISI-027 2CAN022202 Page 1 of 5 REQUEST FOR RELIEF ANO2-ISI-027 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 2
References:
ASME Section XI 2001 Edition with 2003 Addenda, Table IWC-2500-1 ASME Code Case N-460 Examination Category: C-C Item Number(s)
C3.10
==
Description:==
Integral Attachments for Vessels, Piping, Pumps, and Valves Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Second (2nd) Inspection Period I.
CODE REQUIREMENTS ASME Section XI, Table IWC-2500-1, Examination Category C-C, Integral Attachments for Vessels, Piping, Pumps, and Valves:
Item C3.10 requires a surface examination of the Integrally Welded Attachments of Pressure Vessel, as depicted in Figure IWC-2500-5.
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(i), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
III.
BASIS FOR RELIEF During surface examination of the pipe support integral attachment weld, 100%
coverage of the required examination area could not be obtained.
The configuration of the subject component is four 5/8 x 1 x 1 lugs, placed 4 1/16 apart end to end in pairs at 0° and 180° on the vertical pipe. The lugs are integrally welded to the pipe with full penetration welds. The 2 piece 4 wide hanger strap is positioned and bolted between the end to end lugs, contacting the upper lugs which 2CAN022202 Page 2 of 5 support the vertical pipe. Code examination of this type of integral attachment weld requires a surface examination technique, such as Liquid Dye Penetrant or Magnetic Particle Testing, of the weld crown surface and 1/2 inch of base material on either side of the weld toes. However, due to the configuration of this integral attachment and associated hanger strap, access to the weld ends and surrounding base material for examination purposes is limited.
In order to perform additional or alternative Code examinations, modification and/or replacement of the component would be required. The examination performed on the available surface area of the subject item would detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.
IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined the subject items to the extent practical and will continue to perform pressure testing on the subject areas as required by the Code.
V.
CONCLUSION 10 CFR 50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines 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.
Entergy believes that it is impractical to obtain greater examination coverage on these areas. To obtain additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject areas, in addition to the examination of similar welds contained in the program would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Therefore, Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 3 of 5 Table 1 Limited C-C Examinations Component Description Additional Information Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results C3.10 04-009 Steam Generator B South Key Bracket 64 Examination of the required surface as depicted in Figure IWC-2500-5 was limited due to component configuration and limited access to the lower portion of bracket due to permanent insulation support.
Vessel and Bracket are Carbon Steel. Liquid Penetrant surface examination chosen due to limited access.
N/A Surface Exam, Liquid Penetrant (PT)
Limitation due to lower portion of the bracket inaccessibility N/A See attached information (Figures 1 and 1a) derived from PT examination performed in 2R23 and report 2-ISI-PT-14-002 on file at ANO.
Rounded indications (weld porosity) were noted that were acceptable to construction code and ASME Section XI Acceptable 2CAN022202 Page 4 of 5 Figure 1 Coverage for ISI Component 04-009 Not to Scale Key Bracket Weld 2CAN022202 Page 5 of 5 Figure 1a Location sketch and photo for ISI Component 04-009 Not to Scale
2CAN022202 Request for Relief ANO2-ISI-028 2CAN022202 Page 1 of 27 REQUEST FOR RELIEF ANO2-ISI-028 Components /
Numbers:
See Table 1 Code Classes:
American Society of Mechanical Engineers (ASME) Code Class 1
References:
ASME Code Case N-716-1 ASME Code Case N-460 Examination Category: R-A Item Number(s)
R1.11, R1.16, R1.20
==
Description:==
High Safety Significant Class 1 and 2 Piping Welds Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 2 (ANO-2) / Fourth (4th) 10-Year Interval, Second (2nd) and Third (3rd) Inspection Periods I.
CODE REQUIREMENTS ASME Section XI, Code Case N-716-1, Examination Category R-A, Risk Informed Piping Welds:
- 1)
Item R1.11 requires volumetric examination of elements subject to thermal fatigue as depicted in Figure IWB-2500-8(c) and IWB-2500-9, 10, 11.
- 2)
Item R1.16 requires volumetric examination of elements subject to Intergranular or Transgranular Stress Corrosion Cracking as depicted in Figure IWB-2500-8(c) and IWB-2500-9, 10, 11.
- 3)
Item R1.20 requires volumetric examination of elements not subject to a Degradation Mechanism as depicted in Figure IWB-2500-8(c) and IWB-2500-9, 10, 11.
ASME Code Case N-460 allows that a reduction in examination coverage due to interference by another component or part geometry may be accepted provided the reduction in coverage is less 10% (overall coverage is greater than 90%).
II.
RELIEF REQUEST Pursuant to 10 CFR 50.55a(g)(6)(i), Entergy Operations, Inc. (Entergy) requests relief from achieving the Code-required coverage when performing volumetric examinations of the components identified in Table 1.
2CAN022202 Page 2 of 27 III.
BASIS FOR RELIEF During ultrasonic examination of these ASME Section XI, Appendix VIII piping welds listed in Table 1, greater than 90% coverage of the required examination volume could not be obtained. Examinations were performed utilizing EPRI qualified Appendix VIII, Supplement 2 procedures specific to wrought austenitic piping welds.
Due to the geometric configuration and material type of the components, effective volumetric examination could only be performed as noted in the Table 1 for each weld. Although insonification was extended to the far side of the welds to the extent practical, this portion of the examination is not included in the reported examination coverage per the Performance Demonstration Initiative (PDI) and ASME Section XI, Appendix VIII rules. The use of 45, 60° and 70 beam angles in the axial and circumferential direction were not able to achieve greater than 90% code required volume as required by Code Case N-460. See Table 1 for specific information.
Entergy has used the best available and EPRI approved techniques to examine the subject piping welds. To effectively perform any significant additional Code allowable ultrasonic examinations, modification and/or replacement of the component would be required. The examinations performed on the subject items in addition to the examination of other piping welds contained in the Inservice Inspection (ISI) program would detect generic degradation, if it existed, therefore demonstrating an acceptable level of integrity.
As with requests for relief for limited examinations of traditional programs, it is also necessary to complete the interval for a risk-informed program so that all limited examinations can be identified. Once all limited examinations are identified, the cumulative effect of the limited examinations can be determined for each affected system and for the total delta risk.
The following is a summary of the cumulative effect of the limited examinations for each system and total being reported in the relief request.
The eleven welds are contained in three systems. Four welds in the Chemical and Volume Control (CH), five welds in the Reactor Coolant (RCS), and two welds in the Safety Injection (SI).
Chemical and Volume Control (CH) (Welds37-028, 37-029,37-030, and 40-001)
None of the four welds have been selected for in-service examination during the fourth interval as part of the N-716 risk-informed ISI program. While these welds are high safety significant, they were not selected for examination. The four welds examined have no contribution to the delta risk evaluation from not having an in-service examination. The table below provides the delta risk with the four welds credited and with the four welds not credited. The columns under heading Examined include the delta risk with the four welds included. The columns under heading Not Examined include the adjusted delta risk after removing the four welds. As can be seen, there is no change to the result, and this result is below the individual system acceptable limits of 1E-07 for Core Damage Frequency (CDF) and 1E-08 for Large Early Release Frequency (LERF). Therefore, a limited examination of the four CH welds is acceptable.
2CAN022202 Page 3 of 27 Chemical and Volume Control (CH)
CDF Impact LERF Impact Source of Delta Risk w/ POD w/o POD w/ POD w/o POD Examined
-1.01E-09
-4.86E-10
-1.01E-10
-4.86E-11 4th interval periodic update required by N-716 Not Examined
-1.01E-09
-4.86E-10
-1.01E-10
-4.86E-11 Adjusted delta risk using the periodic update delta risk Reactor Coolant (RCS) (Welds43-031, 43-033,28-041, 28-042, and 29-056)
To quantify the effect on delta risk for the five RCS welds, the delta risk is adjusted by not crediting the five RCS welds with limited examination coverage. The table below provides the delta risk with the five RCS welds credited and with the five RCS welds not credited. The columns under heading Examined include the delta risk with the five welds included. The columns under heading Not Examined include the adjusted delta risk after removing the five welds. As can be seen, the change is negligible and well below the individual system acceptable limits of 1E-07 for CDF and 1E-08 for LERF.
Therefore, a limited examination of the five RCS welds is acceptable.
CDF Impact LERF Impact Source of Delta Risk w/ POD w/o POD w/ POD w/o POD Examined
-1.15E-09
-3.60E-10
-1.15E-10
-3.60E-11 4th interval periodic update required by N-716 Not Examined
-1.11E-09
-3.31E-10
-1.11E-10
-3.31E-11 Adjusted delta risk using the periodic update delta risk Safety Injection (SI) (Welds21-007 and 21-001A)
To quantify the effect on delta risk for the two SI welds, the delta risk is adjusted by not crediting the two SI welds with limited examination coverage. The below table provides the delta risk with the two SI welds credited and with the two SI welds not credited. The columns under heading Examined include the delta risk with the two welds included.
The columns under heading Not Examined include the adjusted delta risk after removing the two welds. As can be seen, the change is negligible and well below the individual system acceptable limits of 1E-07 for CDF and 1E-08 for LERF. Therefore, a limited examination of the two SI welds is acceptable.
Safety Injection (SI)
CDF Impact LERF Impact Source of Delta Risk w/ POD w/o POD w/ POD w/o POD Examined 5.56E-09 5.99E-09 5.56E-10 5.99E-10 4th interval periodic update required by N-716 Not Examined 5.57E-09 6.00E-09 5.57E-10 6.00E-10 Adjusted delta risk using the periodic update delta risk 2CAN022202 Page 4 of 27 Cumulative Effect to Delta Risk for All Eleven Welds In the initial request for alternative to use a risk informed program for the fourth interval, the delta risk was provided for each system and cumulatively for all systems. The impact of the limited examination on the delta risk for the individual system is addressed above. The cumulative effect on the total delta risk is provided below. The columns under heading Examined are the delta risk with the eleven welds included. The columns under heading Not Examined is the adjusted delta risk after removing the eleven welds. As can be seen, the change is negligible and well below the total increase acceptable limits of 1E-06 for CDF and 1E-07 for LERF. Therefore, a limited examination of the four CH, five RCS, and two SI welds is acceptable.
Total CDF Impact LERF Impact Source of Delta Risk w/ POD w/o POD w/ POD w/o POD Examined 7.11E-09 8.93E-09 7.11E-10 8.93E-10 4th interval periodic update required by N-716 Not Examined 7.17E-09 8.97E-09 7.17E-10 8.97E-10 Adjusted delta risk using the periodic update delta risk IV.
PROPOSED ALTERNATIVE EXAMINATIONS No alternative testing is proposed at this time. Entergy has examined the subject items to the extent practical and will continue to perform pressure testing on the subject areas as required by the Code.
V.
CONCLUSION 10 CFR 50.55a(g)(6)(i) states:
The Commission will evaluate determinations under paragraph (g)(5) of this section that Code requirements are impractical. The Commission may grant such relief and may impose such alternative requirements as it determines 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.
Entergy believes that it is impractical to obtain greater examination coverage on these areas. To obtain additional coverage would necessitate modification and/or replacement of the component. The examinations performed on the subject areas, in addition to the examination of similar welds contained in the program would detect generic degradation, if it existed, demonstrating an acceptable level of integrity. Therefore, Entergy requests the proposed relief be authorized pursuant to 10 CFR 50.55a(g)(6)(i).
2CAN022202 Page 5 of 27 Table 1 Limited R-A Examinations Component Description Additional Information Item Number Comp.
ID Item Description Estimated Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results R1.11 37-028 Pipe to Valve Circumferential Weld 63 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration. Both the Valve and Pipe are stainless steel.
See the attached information (Figures 1) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-023 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45° and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° angle.
None required No indications were observed or recorded.
Acceptable R1.11 43-031 Tee to Pipe Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the Tee to Pipe component configuration.
Both the Tee and Pipe are stainless steel.
See the attached information (Figures 2 and 2a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-036 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° and 60° angles.
None required No indications were observed or recorded.
Acceptable 2CAN022202 Page 6 of 27 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results R1.11 43-033 Tee to Pipe Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the Tee to Pipe component configuration.
Both the Tee and Pipe are stainless steel.
See the attached information (Figures 3 and 2a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-035 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° and 60° angles.
None required No indications were observed or recorded.
Acceptable R1.16 21-007 Elbow to Valve Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the Elbow to Valve component configuration. Both the Elbow and Valve are stainless steel.
See the attached information (Figures 4 and 4a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-034 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 45°, 60 and 60°L.
Search unit frequencies were 2.00 MHz for 60°L and 2.25 MHz for 45° and 60° angles.
None required No indications were observed or recorded.
Acceptable R1.20 37-029 Valve to Pipe Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration. Both the Valve and Pipe are stainless steel.
See the attached information (Figures 5 and 5a) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-005 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° and 60° angles.
None required 360° Intermittent geometry indications were observed with 70° on far side of weld and recorded.
Acceptable 2CAN022202 Page 7 of 27 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results R1.20 37-030 Pipe to Valve Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration. Both the Valve and Pipe are stainless steel.
See the attached information (Figures 6 and 6a) derived from UT examination performed in 2R24 and report 2-ISI-UT-15-006 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° and 60° angles.
None required 360° Intermittent geometry indications were observed with 70° on far side of weld and recorded.
Acceptable R1.20 40-001 Valve to Pipe Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration. Both the Valve and Pipe are stainless steel.
See the attached information (Figures 7 and 7a) derived from UT examination performed in 2R23 and report 2-ISI-UT-14-021 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45° and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° and 70° angles.
None required No indications were observed or recorded.
Acceptable R1.20 28-041 Tee to Reducer Circumferential Weld 84.8 This is a dual sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration (intrados of the tee). Both the Tee and Reducer are stainless steel.
See the attached information (Figures 8 and 8a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-027 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45°, 60° and 70° angles.
None required No indications were observed or recorded.
Acceptable 2CAN022202 Page 8 of 27 Item Number Comp.
ID Item Description Estimated %
Coverage of Code Required Volume Examination Summary Scan Plan Exam Method and Limitations Search Units Surface Examination Exam Results R1.20 28-042 Elbow to Tee Circumferential Weld 88 This is a dual sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration (Intrados of the tee). Both the Tee and Pipe are stainless steel.
See the attached information (Figures 9 and 8a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-028 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45°, 60 and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45°, 60° and 70° angles.
None required No indications were observed or recorded.
Acceptable R1.20 29-056 Pipe to Tee Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the component configuration. Both the Tee and Pipe are stainless steel.
See the attached information (Figures 10 and 10a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-029 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are shear.
Insonification angles included 45° and 70°.
Search unit frequencies were 2.25 MHz for 70° and 5.0 MHz for 45° angles.
None required No indications were observed or recorded.
Acceptable R1.20 21-001A Elbow to Safe End Circumferential Weld 50 This is a single sided examination.
Examination of the required volume as depicted in Figure IWB-2500-8(c) with Note 1 from ASME Code Case N-716-1 was limited due to the SS Elbow to CASS Safe End configuration.
See the attached information (Figures 11 and 11a) derived from UT examination performed in 2R26 and report 2-ISI-UT-18-031 on file at ANO.
Manual UT.
Scan path limitation due to the configuration of the component.
Wave modalities are longitudinal and shear.
Insonification angles included 45°, 60° and 60°L.
Search unit frequencies were 2.0 MHz for 60°L and 2.25 MHz for 45° and 60° angles.
None required No indications were observed or recorded.
Acceptable 2CAN022202 Page 9 of 27 Figure 1 Scan Plan, Coverage and Location Sketch for ISI Component 37-028 Not to Scale 2CAN022202 Page 10 of 27 Figure 2 Scan Plan and Coverage for ISI Component 43-031 Not to Scale 2CAN022202 Page 11 of 27 Figure 2a Location Sketch for ISI Component 43-031 Not to Scale 2CAN022202 Page 12 of 27 Figure 3 Scan Plan and Coverage for ISI Component 43-033 Not to Scale 2CAN022202 Page 13 of 27 Figure 4 Scan Plan and Coverage for ISI Component 21-007 Not to Scale 2CAN022202 Page 14 of 27 Figure 4a Location sketch for ISI Component 21-007 Not to Scale 2CAN022202 Page 15 of 27 Figure 5 Scan Plan and Coverage for ISI Component 37-029 Not to Scale 2CAN022202 Page 16 of 27 Figure 5a Location sketch for ISI Component 37-029 Not to Scale 2CAN022202 Page 17 of 27 Figure 6 Scan Plan and Coverage for ISI Component 37-030 Not to Scale 2CAN022202 Page 18 of 27 Figure 6a Location Sketch for ISI Component 37-030 Not to Scale 2CAN022202 Page 19 of 27 Figure 7 Scan Plan and Coverage for ISI Component 40-001 Not to Scale 2CAN022202 Page 20 of 27 Figure 7a Location sketch for ISI Component 40-001 Not to Scale 2CAN022202 Page 21 of 27 Figure 8 Scan Plan and Coverage for ISI Component 28-041 Not to Scale 2CAN022202 Page 22 of 27 Figure 8a Location sketch for ISI Component 28-041 and 28-042 Not to Scale 2CAN022202 Page 23 of 27 Figure 9 Scan Plan and Coverage for ISI Component 28-042 Not to Scale 2CAN022202 Page 24 of 27 Figure 10 Scan Plan and Coverage for ISI Component 29-056 Not to Scale 2CAN022202 Page 25 of 27 Figure 10a Location sketch for ISI Component 29-056 Not to Scale 2CAN022202 Page 26 of 27 Figure 11 Scan Plan and Coverage for ISI Component 21-001A Not to Scale 2CAN022202 Page 27 of 27 Figure 11a Location sketch for ISI Component 21-001A Not to Scale