ML20048A006

ASME Section XI Inservice Inspection Program: Relief Request for Limited Coverage Examinations Performed in the Second Period of the Fourth 10-Year Inspection Interval

ML20048A006
Person / Time
Site:	Millstone
Issue date:	02/11/2020
From:	Mark D. Sartain Dominion Energy Nuclear Connecticut
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
19-386
Download: ML20048A006 (33)

Text

Dominion Energy Nuclear Connecticut, Inc.

5000 Dominion Boulevard, Glen Allen, VA 23060 Dominion Dominion Energy.com February 11, 2020 Energy U.S. Nuclear Regulatory Commission Serial No.19-386 Attention: Document Control Desk NRA/SS RO Washington, DC 20555 Docket No. 50--336 License No. DPR-65 DOMINION ENERGY NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2 ASME SECTION XI INSERVICE INSPECTION PROGRAM RELIEF REQUESTS FOR LIMITED COVERAGE EXAMINATIONS PERFORMED IN THE SECOND PERIOD OF THE FOURTH 10-YEAR INSPECTION INTERVAL The Millstone Power Station Unit 2 (MPS2) fourth 10-year interval for the inservice inspection program began on April 1, 2010. During the second inspection period of this interval, the components identified in Attachments 1 through 3 received less than the required examination coverage. Accordingly, pursuant to 10 CFR 50.55a(g)(5)(iii),

Dominion Energy Nuclear Connecticut, Inc. requests relief on the basis that the required examination coverage was impractical due to physical obstructions and limitations imposed by design, geometry and materials of construction of the subject components.

Attachments 1 through 3 contain the specific relief requests and the individual basis for each request. These relief requests have been reviewed and approved by the station's Facility Safety Review Committee.

If you have any questions or require additional information, please contact Shayan Sinha at (804) 273-4687.

Sincerely, Mark D. Sartain Vice President - Nuclear Engineering & Fleet Support

Serial No.19-386 Docket No. 50-336 Page 2 of 2 Attachments:

1. Relief Request RR-04 Examination Category B-D, Full Penetration Welded Nozzles in Vessels - Inspection Program B.

2. Relief Request RR-04-29, Examination Category C-B, Pressure Retaining Nozzle Welds in Vessels.

3. Relief Request RR-04-30, Examination Category R-A, Risk Informed Piping Examinations.

Commitments made in this letter: None cc: U.S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd, Suite 100 King of Prussia, PA 19406-2713 R. V. Guzman Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 08-C 2 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station

Serial No.19-386 Docket No. 50-336 ATTACHMENT 1 RELIEF REQUEST RR-04-28 EXAMINATION CATEGORY B-D FULL PENETRATION WELDED NOZZLES IN VESSELS INSPECTION PROGRAM B DOMINION ENERGY NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

Serial No.19-386 Docket No. 50-336 Attachment 1, Page 1 of 7 10 CFR 50.55a Request Number: RR-04-28 Relief Requested In Accordance with 10 CFR 50.55a(g)(5)(iii)

In-service Inspection Impracticality

1. ASME Code Components Affected:

ASME Code Class: Code Class 1 Examination Category: B-D, Full Penetration Welded Nozzles in Vessels -

Inspection Program B Item Numbers: B3.130, Steam Generator (Primary Side), Nozzle-to Vessel Welds Component Identification: Listed in Table 1 Material: SA508, CL3 Carbon Steel with Internal Stainless Steel Cladding

2. Applicable Code Addition and Addenda ASME Section XI, 2004 Edition, No Addenda

3. Applicable Code Requirement

ASME Section XI, 2004 Edition, Examination Category B-D requires volumetric examination of 100 percent (%) of the weld volume as defined in Table IWB-2500-1 and shown in Figure IWB-2500-7. The alternative requirements of ASME Section XI, Code Case N-460, approved for use in Regulatory Guide 1.147, Revision 18, allows credit for essentially 100% coverage of the welds provided greater than 90%

of the required volume has been examined.

4. Impracticality of Compliance Pursuant to 10 CFR 50.55a(g)(5)(iii), relief is requested from the 100% volumetric examination coverage requirement of the subject welds due to the geometric configuration which limit the volumetric coverage that can be obtained.

The subject steam generator nozzle-to-vessel welds were examined with a manual ultrasonic technique using equipment and procedures written in accordance with ASME Section XI, Appendix 1 and Section V, Article 4 to achieve the maximum examination coverage practical. Limitations imposed by the nozzle configuration

Serial No.19-386 Docket No. 50-336 Attachment 1, Page 2 of 7 preclude obtaining 100% coverage. This configuration with the nozzle outside radius within close proximity of the weld prevents complete scanning in these areas due to lift-off of the search unit that occurs causing a loss of contact between the search unit and the component.

The required examination volume of these welds was interrogated ultrasonically to the maximum extent possible. No alternative techniques or advanced technologies were considered capable of obtaining complete coverage of the examination volume.

Isometric drawing and coverage calculations are provided in this attachment.

TABLE 1- Examination Category B-D Welds with Limited Volumetric Coverage

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Scan limitations due to 0° Long Wave 30" Cold Leg configuration of 30° Shear Wave SG-1-NH-2-A B3.130 Nozzle to the nozzle. No 72.4%

45° Shear Wave Hemisphere recordable 60° Shear Wave indications were detected.

Scan limitations due to 0° Long Wave 42'1 Hot Leg configuration of 30° Shear Wave SG-1-NH-4-A B3.130 Nozzle to the nozzle. No 72.5%

45° Shear Wave Hemisphere recordable 60° Shear Wave indications were detected.

Scan limitations

° due to 0 Long Wave 30" Cold Leg configuration of 30° Shear Wave SG-1-NH-5-A B3.130 Nozzle to the nozzle. No 72.4%

45° Shear Wave Hemisphere recordable 60° Shear Wave indications were detected.

5. Burden Caused by Compliance To increase examination coverage on the subject welds would require a significant design modification or replacement of components with a different design to

Serial No.19-386 Docket No. 50-336 Attachment 1, Page 3 of 7 eliminate the noted obstructions. This is considered impractical due to cost, increased radiation exposure, and impact to plant equipment.

6. Proposed Alternative and Basis for Use The subject welds received a volumetric examination to the maximum extent practical. Additionally, these components are monitored for through-wall leakage as part of the ASME Section XI System Pressure Test Program and receive a visual (VT-2) examination at the end of each refueling outage during the system leakage tests required by Section XI, Table IWB-2500-1, Category B-P for class 1 components.

Based upon the examination volumes that were obtained with acceptable results along with the visual (VT-2) examination performed each refueling outage, it is reasonable to conclude that service-induced degradation would be detected.

Therefore, these proposed alternatives will provide an acceptable level of quality and safety by providing reasonable assurance of structural integrity of the subject welds.

7. Duration of Proposed Alternative The relief is requested for the fourth ten-year inspection interval for Millstone Power Station Unit 2, which began on April 1, 2010 and will end March 31, 2020.

8. Precedent A similar relief request was approved for use at MPS2 during the first period of the fourth 10-year ISi interval (i.e., Relief Request RR-04-17 (ADAMS Accession No. ML16172A135)).

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I ase metal exam 9.1707"= 56.5% 0° Subtotal:

0°= 64.8%

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Total Code Exam Volume essel = 16.9030" Weld Subtotal:

us 30°°= 58.6%

DS30 = 100%

30° USWeld 0° DSWeld eld = 7.7322" us 45°° = 36.8%

4.5289" 58.6% 7.7322"= 100% ozzle = 17.0054" DS45 = 97.4%

otal = 41.6406" us 60°°= 22.4%

DS60 = 65.4%

30° cw = 100%

30° ccw = 100%

n exam area 0 45° CW= 100%

26.9827"= 64.8% 45° CCW = I 00%

fTT7145° DSWeld Total= 780.6 / 10= 78.1%

45° USWeld 2.8460"= 36.8% 7.5277"= 97.4% Base metal Subtotal:

Axial 30° / 45° / 6 0°= 94.1%

Circ umferential 30° / 45 °= 56.5%

Total = 150.6 / 2= 75.3%

ITTTT"t"0° CW Weld 100%

30° CCW Weld 100% Coverage Total: m 60° USWeld 0 DSWeld

° 45° CW Weld 100% 64.8 + 78.l + 75.3= 217.2 I 3= 72.4% C)

J" 1.7311" = 22.4% .0549"= 65.4% 45° CCW Weld 100% CD (/)

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Coverage Total:

x Angle a'lial direction 6.52 6.62 6.6S 6,6! 6,70S 6.69 6.70 6.S6 6.19 S.95 0° Subtotal:

ase metal exam 0°=64.6%

5.7198"= 90.8%

Weld Subtotal:

DS30° =44.8%

us 30°°=100%

DS45 =27.6%

us 45°=100%

DS60°=16.3%

us 60°=100%

cw30°=100%

" ngle CW/CCW CCW 30° = I 00%

I);ase metal exam FIOW' cw45°=100%

8.7921"= 57.2% ccw45 °=100%

0 71 ' ' 0 Total Code Exam Vol ume I ' L -essel=25.5760" Total= 788.7 /IO=78.9%

eld= 10.3817" ozzle=24.7578" Base metal Subtotal:

otal=60.7155" Axial 30° / 45 ° / 60°= 90.8%

j Cir c umferential 30° / 45° = 57.2%

Total=148 / 2= 74%

30DSWeld Coverage Total:

4.6533" - 44.8%

" 64.6 + 78.9 + 74 =217.5 / 3 =72.5%

\} r-, exam area 9.2313"=64.6%

Scale 1:6 45DSWeld r777]45 USWeld Area dimensions determined 2.8646"=27.6%

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19.1707"=56.5% 0° Subtotal:

0°=64.8%

Weld Subtotal:

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us 30°° = 58.6%

essel=16.9030" DS30 =100%

30° USWeld 130° DSWeld eld=7.7322" us 45°°=36.8%

4.5289" - 58.6% 7.7322"=100% ozzle=17.0054" DS45 = 97.4%

otal=41.6406" us 60°° = 22.4%

DS60 = 65.4%

30° CW=100%

30 ° ccw=100%

n0 exam area 45° CW=100%

26.9827" = 64.8% 45° ccw = 100%

Total=780.6 / 10=78.1%

45° USWeld rT'77145° DSWeld 7.5277"=97.4%

2.8460" =36.8% Base metal Subtotal:

Axial 30° / 45° / 6 0°=94.1%

Circ umferential 30 ° / 45°= 56.5%

Total=150.6 I 2 = 75.3%

30° CW Weld 100%

1 30° CCW Weld 100% Coverage Total:

60° USWeld 0 ° DSWeld 45° CW Weld 100% 64.8 + 78.1 + 75.3=217.2 I 3 = 72.4% Ol

.0549" =65.4% (')

1.7311"=22.4% 45° CCW Weld 100% :J'"

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Serial No.19-386 Docket No. 50-336 ATTACHMENT 2 RELIEF REQUEST RR-04-29 EXAMINATION CATEGORY C-8 PRESSURE RETAINING NOZZLE WELDS IN VESSELS DOMINION ENERGY NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

Serial No.19-386 Docket No. 50-336 Attachment 2, Page 1 of 8 10 CFR 50.55a Request Number: RR-04-29 Relief Requested In Accordance with 10 CFR 50.55a(g)(5)(iii)

In-service Inspection Impracticality

1. ASME Code Components Affected:

ASME Code Class: Code Class 2 Examination Category: C-B, Pressure Retaining Nozzle Welds in Vessels Item Numbers: C2.21, Nozzle-to-Shell (Nozzle-to-Head or Nozzle-to-Nozzle) Weld Component Identification: Listed in Table 1 Material: SA533, GR B carbon steel

2. Applicable Code Addition and Addenda ASME Section XI, 2004 Edition, No addenda

3. Applicable Code Requirement

ASME Section XI, 2004 Edition, Category C-B requires volumetric examination of 100 percent (%) of the weld volume as defined in Table IWC-2500-1 and shown in Figure IWC 2500-4. The alternative requirements of ASME Section XI, Code Case N-460, approved for use in Regulatory Guide 1.147, Revision 18, allows credit for essentially 100% coverage of the welds provided greater than 90% of the required volume has been examined.

4. Impracticality of Compliance Pursuant to 10 CFR 50.55a(g)(5)(iii), relief is requested from the 100% volumetric examination coverage requirement of the subject welds due to the geometric configuration and permanent obstructions which limit the volumetric coverage that can be obtained.

The subject steam generator nozzle welds were examined with a manual ultrasonic technique using equipment and procedures written in accordance with ASME Section XI, Appendix 1 and Section V, Article 4 to achieve the maximum examination coverage practical. Limitations imposed by the nozzle configuration preclude obtaining 100% coverage. This configuration with the nozzle outside

Serial No.19-386 Docket No. 50-336 Attachment 2, Page 2 of 8 radius within close proximity of the weld prevents complete scanning in these areas due to lift-off of the search unit that occurs causing a loss of contact between the search unit and the component. An additional limitation was encountered with the examination of the main steam nozzle to head weld (SG-2-MS-1) due to six permanently welded insulation retaining lugs that are located within close proximity of the weld that restricts the scanning in these areas on the head side of the weld.

The required examination volume of these welds was interrogated ultrasonically to the maximum extent possible. No alternative techniques or advanced technologies were considered capable of obtaining complete coverage of the examination volume.

Weld isometric drawing, coverage calculations and limitation sketches are provided in this attachment.

Serial No.19-386 Docket No. 50-336 Attachment 2, Page 3 of 8 TABLE 1- Examination Category C-B Welds with Limited Volumetric Coverage SG-1-FW-1 (2.21 Feed Water oo Long. Wave Scan Limitations due to the 88.8% Magnetic particle 45 ° Shear Wave configuration of the nozzle examination Steam Generator 60° Shear Wave restricting the scans from the performed obtaining No. 1 Feed Water nozzle side of the weld. 100% coverage. No Nozzle to Shell Weld recordable No recordable indications were indications detected.

detected.

SG-2-MS-1 (2.21 Main Steam 0° Long. Wave Scan Limitations due to the 73.6% Magnetic particle 45 ° Shear Wave configuration of the nozzle examination Main Steam Nozzle 60° Shear Wave restricting the scans from the performed obtaining to Head Weld nozzle side of the weld. 100% coverage. No Additional limitation from the recordable head side of the weld due to six indications detected.

permanently welded insulation retaining lugs located within close proximity of the weld.

No recordable indications were detected.

Serial No.19-386 Docket No. 50-336 Attachment 2, Page 4 of 8

5. Burden Caused by Compliance To increase examination coverage on the subject welds would require a significant design modification or replacement of components with a different design to eliminate the noted obstructions. This is considered impractical due to cost, increased radiation exposure, and impact to plant equipment.

6. Proposed Alternative and Basis for Use The subject welds received a volumetric examination to the maximum extent practical. Additionally, these components are monitored for through-wall leakage as part of the ASME Section XI System Pressure Test Program and receive a visual (VT-2) examination at the end of each inspection period during the system leakage tests required by Section XI, Table IWC-2500-1, Category C-H for class 2 components.

Based upon the examination volumes that were obtained with acceptable results along with the visual (VT-2) examination performed each inspection period, it is reasonable to conclude that service-induced degradation would be detected.

Therefore, these proposed alternatives will provide an acceptable level of quality and safety by providing reasonable assurance of structural integrity of the subject welds.

7. Duration of Proposed Alternative The relief is requested for the fourth ten-year inspection interval for Millstone Power Station Unit 2, which began on April 1, 2010 and will end March 31, 2020.

8. Precedent A similar relief request was approved for use at MPS2 during the third 10-year ISi interval (i.e., Relief Request RR-89-73 (ADAMS Accession No. ML120541062)).

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Weld ID: SG-1-FW-1 aLL:t Nozzle 4.915 4.910 45° 60° Vessel 45° OS (US skip)Wel 5°USWeld Y7,7].1"*100%

V/1 TotalCode Exam Volume 3.l" Coverage Total:

0°=0%

45 us = 100%

l.l"*I0W< [LLJ 45 OS = 100%

45CW = 100%

45CCW=100%

60US= 100%

0 exam area 60DS= 100% Ol 60° OS (US skip) we1 0° us Weld 60CW = 100% (")

l.1"*1003/4 r771.1"*100% 0.0"=0%  :::J" 60CCW= 100% 3 45°CWWeld 100%

45° CCWWeld 100%

Total: 800 / 9 =88.8% Cl) 2? (/)

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Weld ID: SG-2-MS-1 (tfl 45 Coverage Total 0 Planar 100.0%

45 Upstream 81.4%

45 Downstream 0.0%

45 Clockwise 100.0%

45 Counterclockwise 100.0%

4.86" 60 Upstream Xl.4%

60 Downstream 0.0%

60 Clockwise 100.0%

60 Countcrclockwic 100.0%

Total: 662.8%/9= 73.6%

Total examination volume= 96.75" (Weld Length) x 3.44square inches (Weld volume)= 332.82 cubic inches Ins. Lug_

Examined 100% orrcquired volume with 0 planar, 45 CW&CCW, 60 CW&CCW Total examination volume= 96.75" (Weld Length) x 3.44square inches (\.Veld volume)= 332.82.cubic inches L

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332.82 cubic inches - ( 18" x 3.44 squaure inches)= 270.9 cubic inches examined 270.9/332.83= 81.4% examined

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Serial No.19-386 Docket No. 50-336 ATTACHMENT 3 RELIEF REQUEST RR-04-30 EXAMINATION CATEGORY R-A RISK INFORMED PIPING EXAMINATIONS DOMINION ENERGY NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 2

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 1 of 13 10 CFR 50.55a Request Number: RR-04-30 Relief Requested In Accordance with 10 CFR 50.55a(g)(5)(iii)

In-service Inspection Impracticality

1. ASME Code Components Affected:

ASME Code Class: Code Class 1 and 2 Examination Category: R-A, Risk-Informed Piping Examinations Item Numbers: R1.11, Elements Subject to Thermal Fatigue R1.20, Elements not Subject to a Degradation Mechanism R1.16, Elements Subject to lntergranular or Transgranular Stress Corrosion Cracking (IGSCC or TGSCC)

Component Identification: Listed in Table 1 Material: Type 316 Austenitic Stainless Steel or SA106 GR B Carbon Steel (as shown in Table 1) with Stainless Steel or Carbon Steel type weld filler metal. The subject welds contain no Alloy 600/82/182 material.

2. Applicable Code Addition and Addenda ASME Section XI, 2004 Edition, No Addenda

3. Applicable Code Requirement

The examination requirements for Class 1 and Class 2 piping welds are governed by the risk-informed In-Service Inspection program that was approved by the NRC in a letter dated March 27, 2012 (ADAMS Accession Number ML120800433). The program was developed in accordance with ASME Code Case N-716, "Alternative Piping Classification and Examination Requirements."

Code Case N-716, Table 1, Examination Category R-A, requires that essentially 100 percent (%) of the weld volume be examined. The alternative requirements of ASME Code Case N-460, approved for use in Regulatory Guide 1.147, Revision 18, allows credit for essentially 100% coverage provided greater than 90% of the required volume has been examined.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 2 of 13 10 CFR 50.55a(b)(2)(xv)(A), requires the following examination coverage criteria when applying Supplement 2 (Qualification Requirements for Wrought Austenitic Piping Welds) to Section XI Mandatory Appendix VIII (Performance Demonstration for Ultrasonic Examination Systems):

(1) Piping must be examined in two axial directions and when examination in the circumferential direction is required, the circumferential examination must be performed in two directions, provided access is available.

(2) Where examination from both sides is not possible, full coverage credit may be claimed from a single side for ferritic welds. Where examination from both sides is not possible on austenitic welds, full coverage credit from a single side may be claimed only after completing a successful single sided Appendix VIII demonstration using flaws on the opposite side of the weld.

10 CFR 50.55a(b)(2)(xvi)(B), requires that examinations performed from one side of a ferritic or stainless steel pipe weld must be conducted with equipment, procedures, and personnel that have demonstrated proficiency with single side examinations. To demonstrate equivalency to two-sided examinations, the demonstration must be performed to the requirements of Appendix VIII, as modified by this paragraph and 10 CFR 50.55a(b)(2)(xv)(A).

4. Impracticality of Compliance Pursuant to 10 CFR 50.55a(g)(5)(iii), relief is requested from the 100%

volumetric examination coverage requirement for the subject austenitic welds due to the geometric configuration which limits the volumetric coverage that can be obtained.

The subject welds were examined with a manual ultrasonic technique utilizing personnel, equipment and procedures qualified in accordance with ASME Section XI, Appendix VIII as implemented by the Performance Demonstration Initiative (POI).

There are currently no POI qualified single side examination procedures that demonstrate equivalency to two-sided examination procedures on austenitic piping welds. Current technology is not capable of reliably detecting or sizing flaws on the far side of an austenitic weld for configurations common to domestic nuclear applications.

POI Performance Demonstration Qualification Summary (PDQS) certificates for austenitic piping list the limitation that single side examination is performed on a

• best effort basis. The best effort qualification is provided in place of a complete single side qualification to demonstrate that the examiners qualification and the subsequent weld examination is based on application of the best available technology.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 3 of 13 When the examination area is limited to one side of an austenitic weld, examination coverage does not comply with 10 CFR 50.55a(b)(2)(xv)(A) and proficiency demonstrations do not comply with 10 CFR 50.55a(b)(2)(xvi)(B) and full coverage credit may not be claimed.

The ASME code required volume of these welds was interrogated ultrasonically to the maximum extent possible. No alternative methods or advanced technologies, including the use of phased array, were considered capable of obtaining complete coverage of the examination volume.

The subject welds consist of a pipe-to-valve or pipe-to-tee configuration in which the tapered surface of the valve or the branch of the tee is within close proximity of the weld and limit the ability to scan from that side of the weld.

There are no welds in this request that are within the scope of the Electric Power Research Institute (EPRI) document MRP-146 (Management of Thermal Fatigue in Normally Stagnant Non-lsolable Reactor Coolant System Branch Lines) requirements.

Based on the configuration limited to single sided access, relief is requested from complying with the 100% required examination coverage for the piping welds listed in Table 1. Note that examination coverage listed in Table 1 is that which was obtained during examination with no credit taken for the far side of each weld.

Supplemental scanning was performed to provide additional best effort (non code) coverage as documented on the enclosed coverage calculation for each weld.

Coverage calculations are provided in this attachment.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 4 of 13 Table 1- Examination Category R-A Welds with Limited Volumetric Coverage System / Code Class Weld Code Examination Angle and Exami.nation I Configuration I Limitations and Results Identification Item# Wave Mode Coverage(%)

Materi.al BCH-C-1007A Rl.11 I Charging/ Class 1 45 ° Shear Wave Examination is limited on the upstream 82.5%

45 ° Shear Wave side due to Tee configuration. The branch 2" Pipe-to-Tee 60° Shear Wave of the Tee is within close proximity of the Type 316 Stainless Steel, I 70

° Shear Wave weld. There is not sufficient distance from Schedule 160 the weld to the Tee to perform any scanning on the Tee side of the weld No recordable indications were detected.

BSI-C-3010-A Rl.16 Safety Injection/ Class 1 45° Shear Wave This was a pre-service examination 50%

60° Shear Wave associated with a new weld. Examination 12" Pipe-to-Valve 60° Long Wave is limited to the pipe side only due to the Type 316 Stainless Steel, taper of the valve being within close Schedule 140 proximity of the weld. There is not sufficient distance from the weld to the valve to perform any scanning on the valve side of the weld.

No recordable indications were detected.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 5 of 13 System I Code Clc1ss Weld Code Examination Angle and Examiha{ion Configuration Limitati.ons and Results Identification I. Item# Wave Mode Coverage (%)

Material BSI-C-3012-A Rl.16 Safety Injection/ Class 1 45° Shear Wave This was a pre-service examination 50%

I 60° Long Wave associated with a new weld. Examination 12" Pipe-to-Valve is limited to the pipe side only due to the Type 316 Stainless Steel, taper of the valve being within close Schedule 140 proximity of the weld. There is not sufficient distance from the weld to the valve to perform any scanning on the valve side of the weld.

No recordable indications were detected.

BPV-C-5104A Rl.20 Reactor Coolant/ Class 1 I 45° Shear Wave Examination is limited due to Tee 89.5%

70° Shear Wave configuration. The branch of the Tee is 4" Pipe-to-Tee within close proximity of the weld. There Type 316 Stainless Steel, is not sufficient distance from the weld to Schedule 120 the Tee to perform any scanning on the Tee side of the weld.

No recordable indications were detected.

FWB-C-G-17-A Rl.20 Main Feedwater/ Class 2 45° Shear Wave This was a pre-service examination 81.2%

60° Shear Wave associated with a new weld. Examination 6" Pipe-to-Valve Shear Wave is limited to the pipe side only due to the 70° SA106 GR B Carbon taper of the valve being within close Steel, Schedule 40 proximity of the weld. There is not sufficient distance from the weld to the valve to perform any scanning on the valve side of the weld. One recordable indication was detected which was evaluated as acceptable weld root geometry.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 6 of 13 System I Code Class Weld Code El3ri1intion Angle and Examination Configuration Limitations and Results Identification Item# WaveMode Coverage(%)

Material SI-CF-O-035 Rl.20 High Pressure Safety 45 ° Shear Wave This was a pre-service examination 50%

1 ° Injection/ Class 1 70 Shear Wave associated with a new weld. Examination is limited to the pipe side only due to the 3" Pipe-to-Valve taper of the valve being within close Type 316 Stainless Steel, proximity of the weld. There is not Schedule 160 sufficient distance from the weld to the valve to perform any scanning on the valve side of the weld.

One recordable indication was detected which was evaluated as acceptable weld root geometry.

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 7 of 13

5. Burden Caused by Compliance Compliance with the Code requirements would require extensive modification or replacement of components with a design that would allow full examination from both sides of the weld. This is considered impractical based on cost, increased radiation exposure, and impact to plant equipment.

6. Proposed Alternative and Basis for Use The subject welds received a volumetric examination to the maximum extent practical utilizing the best available techniques, as qualified through the POI for Supplement 2, with demonstrated best effort for single sided examination from the accessible side of the weld. Also, these components are monitored for through-wall leakage as part of the ASME Section XI System Pressure Test Program and receive a visual (VT-2) examination at the end of each refueling outage during the system leakage tests as required by Section XI, Table IWB-2500-1, Category B-P for Class 1 components and Table IWC-2500-1, Category C-H for Class 2 components.

Based on the volumetric coverage that was obtained with acceptable results and the visual (VT-2) examination performed each refueling outage, it is reasonable to conclude that service-induced degradation would be detected. Therefore, these proposed alternatives will provide an acceptable level of quality and safety by providing reasonable assurance of structural integrity of the subject welds.

7. Duration of Proposed Alternative Relief is requested for the fourth ten-year inspection interval for Millstone Power Station Unit 2, which began on April 1, 2010 and ends March 31, 2020.

8. Precedent A similar relief request was approved for use at MPS2 during the first period of the fourth 10-year ISi interval (i.e., Relief Request RR-04-19 (ADAMS Accession No. ML16172A135)).

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 8 of 13 Coverage Summary-Weld# BCH-C-1007A R eport No: I Summary: I Page: I By: I D ate:

MT-2-UT-15-008 I M2.R11.0055 I 5 of6 I D.R. Cordes/ LIii I 10/10/15 Examination Volume Dimensions: Length 4.7" x Width 1.50" K Height .12" Weld Thickness= 0.36" Weld Length= 4.7" Weld Width= 0.5"

,/Flow

° 45 °/70 ° (max W2 position) 45 ° 70 Pipe '(  ;?s;i?

'\{A Tee Body

__.- '- Area 3 -.._

Required Examination Volume- 0.18 Sq" Area I (1.50" x 0.12" = 0.18 Sq" or 0.09 Sq" per side)

Area oflimitation (tee config) - 0.062 Sq" (0.09 - 0.62) I 0.9= 31. l %

Supp 70° - (Up scan for Dn scan credit - best effort) L:::::::::... Area 3 Obtained additional 0.014 sq in on tee side 0.014/0.09= 15.5%

Required Scans- each has a weighing factor of 100% for complete coverage Angle Upstream-Axial Upstream- Circ. Downstream Axial Downstream Circ.

45°/70° 31% 100% 100% 100%

70°-Best Effort 15.5% N/A N/A N/A 31+1oo+100+100=331/4=82.50% Code Coverage Total 82.5%

34.9+1oo+1oo+100=83.3% Best Effort Coverage (Max 25%) Total 3.9% (Tee Side)

Notes:

1. Code Coverage refers to the maximum percentage of the required examination volume that is effectively examined with the qualified examination procedure

2. Best Effort Coverage refers to the required examination volume past the centerline that is examined in the axial beam direction with an Appendix VIII demonstrated procedure for single sided coverage (Area dimensions determined with Turbocad)

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 9 of 13 Valve FLOW Pipe 1.242" 1.275" 1.200" 1.200" 60° 45 ° 60° RL L__

Required Examination Volume:

0.9184 Sq. Inches Far Side Examination Volume:

0.4458 Sq. Inches Best Effort Examination Volume:

0.4187 Sq. Inches Far side examination volume limited due to single sided access.

Limited area scanned with 2.0 MHZ 60 degree for best effort coverage.

(Area dimensions determined with Turbo CAD 18)

Examination Volume Dimensions: Length 40.75" x Width 2.1" X Height 0.414" Weld Thickness= 1.24" Weld Length= 40.75" Weld Width= 1.1" Coverage Summary- Weld# BSI-C-3010-A Required Scans- each has a weighing factor of 100% for complete coverage Angle Upstream-Axial Upstream- Circ. Downstream Axial Downstream Circ.

45/60

° 100% 100% 0% 0%

° 60 RL 93.9% (BEST EFFORT)

Code Coverage Total 50%

(100+100+0+0)/4=50% Best Effort Coverage (Max 25%) Total 23.4%

Notes:

1. Code Coverage refers to the maximum percentage of the required examination volume that is effectively examined with the qualified examination procedure

2. Best Effort Coverage refers to the required examination volume past the centerline that is examined in the axial beam direction with an Appendix VIII demonstrated procedure for single sided coverage

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 10 of 13 Flow 1.13 1.15 1.14 1.17 1.19 NR Valve 45° Required Exam Volume -.7478 Sq. in (1.90*.39= .741 Sq. in)

Far Side Required Exam Volume - .3702 Sq. In

(.95*.39 = .3705 Sq. in)

Volume Examined on Far Side - .3702 Sq. in (100%)

(Best Effort)

(Area dimensions determined with TurboCAD 19)

Examination Volume Dimensions: Length 40.25" x Width 1.90" x Height .39" Weld Thickness= 1.17" Weld Length= 40.25" Weld Width= .90" Coverage Summary- Weld # BSI-C-3012-A Required Scans- each has a weighing factor of 100% for complete coverage Angle Upstream-Axial Upstream- Clrc. Downstream Axial Downstream Circ.

45 100% 100% 0% 0%

60 100%(Best Effort)

Code Coverage Total 50%

100+100+100+0=300/4=75% Best Effort Coverage (Max 25%) Total 25%

Notes:

1. Code Coverage refers to the maximum percentage of the required examination volume that Is effectively examined with the qualified examination procedure

2. Best Effort Coverage refers to the required examination volume past the centerline that is examined in the axial beam direction with an Appendix VIII demonstrated procedure for single sided coverage

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 11 of 13 Coverage Summary - Weld # BPV-C-5104A Report No: I Summary: I Page: I By: I Date:

M2-UT-15-00S I M2.R1.20.0024 I 3 of 4 I D.R. Cordes / LIii I 10/13/15 Examination Volume Length 14.2" X Width 1.80" X Height 0.15" Dimensions:

Thickness= 0.44" Weld Length= 14.2" Weld Width= 0.8" Limited Ax Dn scan of 6" (3" on each side oftee "radius" area)

Flow (Flush) 0.6" 0.53" 0.44" Tee 0.53" 0.44" Pipe (T&C from 2006 Data)

Required Examination Volume- 0.354 Sq. In."

Irregular. Determined by CAD 0.354 sq in in. 0.138(pipe)/0.216(tee)

[

0.354 sq in x 14.2 = 5.03 Total Vol 0.138x 14.2 = 1.96 Vol Pipe side 0.216 x 14.2=3.07 Vol Tee side 0.216x14.2x0.9=2.76 Supp 70° - (Up scan for Dn scan credit - best effort)

Irregular - determined by CAD (tee limitation) 0.216" I 3.07= 7%

0.216 X 6 X 0.9 = 1.17 1.17/ 2.76 = 42%

Required Scans- each has a weighing factor of 100% for complete coverage '

Angle Upstream-Axial Upstream- Circ. Downstream Axial Downstream Circ.

45 ° 100% 100% 58% 100%

70°-Best Effort N/A N/A 42% (from Pipe) N/A 100+10o+58+100=358.6/4=89.5% Code Coverage Total 89.5%

100+100+100+100=400/4=100% Best Effort Coverage {Max 25%) Total 10%

Notes:

1. Code Coverage refers to the maximum percentage of the required examination volume that is effectively examined with the qualified examination procedure

2. Best Effort Coverage refers to the required examination volume past the centerline that is examined in the axial beam direction with an Appendix VIII demonstrated procedure for single sided coverage (Area dimensions determined with Turbocad)

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 12 of 13

/ Flow NR NR .324" .290" .281" Valve Pipe Required Examination Volume = .17 Sq. in

(.10*1.50 =.15 Sq. in 01111111110 Far Side Required Exam Volume - .08 Sq. in

(.75"*.10 = .08 Sq. in)

No Coverage _____-,,

IU Volume Examined on Far Side - .02 Sq. in (25%)

(Area dimensions determined with TurboCAD 19)

Examination Volume Dimensions: Length 21.0" x Width 1.50" X Height .10" Weld Thickness= .324" Weld Length= 21.0" Weld Width= .SO" Coverage Summary- Weld# FWB-C-G-17-A Required Scans- each has a weighing factor of 100% for complete coverage Angle Upstream-Axial I Upstream- Clrc. I Downstream Axial I Downstream Circ.

45 °/60°/70° 100% I 25% I 100% I 100%

Code Coverage Total I 81.2%

(100+2s%+100+100)14= I Best Effort Coverage (Max 25%) Total I N/A Notes:

1. Code Coverage refers to the maximum percentage of the required examination volume that is effectively examined with the qualified examination procedure

Serial No.19-386 Docket No. 50-336 Attachment 3, Page 13 of 13 Flow

.50 .47 .46 .45 .45 Valve 45° Pipe Required Exam Volume -.2717 Sq. in txX><XXXXXXXX>© (1.60*.16= .256 Sq. in)

Far Side Required Exam Volume- .1471 Sq. In fn1//Zl

(.80*.16= .128 Sq. in)

Volume Examined on Far Side - .1256 Sq. in (85%) ir::?Z,1//21 (Best Effort)

(Area dimensions determined with TurboCAD 19)

Examination Volume Dimensions: Length 11.4" x Width 1.60" X Height .16" Weld Thickness= .SO" Weld Length= 11.4" Weld Width= .60" Coverage Summary- Weld# SI-CF-D-03S(W26)

Required Scans- each has a weighing factor of 100% for complete coverage Angle Upstream-Axial Upstream- Circ, Downstream Axial Downstream Circ.

45 0% 0% 100% 100%

70 85%(Best Effort)

Code Coverage Total 50%

0+85+100+100=285/4=71% Best Effort Coverage (Max 25%) Total 21%

Notes:

l. Code Coverage refers to the maximum percentage of the required examination volume that is effectively examined with the qualified examination procedure

2. Best Effort Coverage refers to the required examination volume past the centerline that is examined In the axial beam direction with an Appendix VIII demonstrated procedure for single sided coverage