ML101930245

American Society of Mechanical Engineers Code Required Weld Inspections Relief Requests

ML101930245
Person / Time
Site:	Calvert Cliffs
Issue date:	06/30/2010
From:	John Stanley Calvert Cliffs, Constellation Energy Nuclear Group, EDF Group
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML101930245 (31)

Text

Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 CENG a joint venture of A% Constellation *'~eDF

%0 Energy D CALVERT CLIFFS NUCLEAR POWER PLANT June 30, 2010 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION: Document Control Desk

SUBJECT:

Calvert Cliffs Nuclear Power Plant Unit Nos. 1 & 2; Docket Nos. 50-317 & 50-318 American Society of Mechanical Engineers Code Required Weld Inspections Relief Reauests In accordance with 10 CFR 50.55a(g)(5)(iii), Calvert Cliffs Nuclear Power Plant, LLC requests relief from the performance of selected American Society of Mechanical Engineers code required weld inspections. These inspections were scheduled to be performed during the recently completed Third Ten-Year Inservice Inspection Program Plan period. Relief is requested due to the determination that complete performance of these weld inspections is impractical. Justifications for these four relief requests are contained in Attachments (1) thru (4).

These relief requests are submitted under the provision of 10 CFR 50.55a(3)(ii) in that performance of these inspections, in compliance with American Society of Mechanical Engineer requirements, would result in unusual difficulty without a compensating increase in the level of quality and safety.

Should you have questions regarding this matter, please contact Mr. Douglas E. Lauver at (410) 495-5219.

Very truly yours, for James J. Stanley Manager - Engineering JJS/KLG/bjd

Attachment:

(1) Relief Request ISI-24 for CCNPP Unit 1 Class 1 Components (2) Relief Request ISI-25 for CCNPP Unit 1 Class 2 Components (3) Relief Request ISI-26 for CCNPP Unit 2 Class 1 Components Relief Request ISI-27 for CCNPP (4) Unit 2 Class 2 Components A-C)CP

",(UZ

Document Control Desk June 30, 2010 Page 2 cc: D. V. Pickett, NRC Resident Inspector, NRC S. J. Collins, NRC S. Gray, DNR

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS Calvert Cliffs Nuclear Power Plant, LLC June 30, 2010

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS

1. ASME Code Component(s) Affected ASME Code Class 1 Examination Categories: B-D and R-A Item Numbers: B3.110, B3.130, R1.16, and R1.20

2. Applicable Code Edition and Addenda

American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section XI, 1998 Edition, no Addenda.

3. Applicable Code Requirement

American Society of Mechanical Engineers Code,Section XI, Sub-article IWB-2500 states in part, "Components shall be examined and tested as specified in Table IWB-2500-1." Table IWB-2500-1 requires an examination of applicable Class 1 pressure retaining-welds, which includes essentially 100% of the weld length once during the ten-year interval for Code Category B-D, Item Numbers B3.1 10 and B3.130.

A risk-informed in-service inspection (RI-ISI) program was approved for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs) by the Nuclear Regulatory Commission (NRC) on April 16, 2003. The RI-ISI was developed for Class 1 and 2 piping welds for the Examination Category B-F, B-J, C-F-i, and C-F-2 circumferential piping welds in a manner consistent with ASME Code,Section XI, Code Case N-578. Code Case N-578 examination requirements are listed in Table I, Examination Category R-A, Item No. RL. I (TASCS), Rl.16 (IGSCC), and R1.20 (No Degradation Mechanism),

and require essentially 100% of the required volume of the weld and adjacent base material to be examined.

Code Case N-460 permits a reduction in examination coverage of Class I and Class 2 welds provided the coverage reduction is less than 1.0%. Calvert Cliffs has adopted Code Case N-460 in the Inservice Inspection (ISI) Program Plan, as permitted by NRC Regulatory Guide 1.147, Revision 15.

4. Impracticality of Compliance c

Title 10 CFR 50.55a recognizes the limitations to in-service inspection of components in accordance with Section XI of the ASME Code that are imposed due to early plant design and construction, as follows: 10 CFR 50.55a(g)(1), "For a boiling or pressurized water-cooled nuclear power facility whose construction permit was issued prior to January 1,. 1971, components (including supports) must meet the requirements of paragraphs (g)(4) and (g)(5) of this section to the extent practical,"

Title 10 CFR 50.55a(g)(4) states, "Throughout the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports) which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements, except design and access provisions and preservice examination requirements, set forth in Section XI of Editions of the ASME Boiler and Pressure Vessel Code ... to the extent practical within the limitations of design, geometry and materials of construction of the components."

Further, 10 CFR 50.55a(g)(5)(iii) states that, "If the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in § 50.4, information to support the determinations."

1

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS Calvert Cliffs has determined that the following welds (shown in Table 1 below) were limited from achieving greater than 90% of the required examination volume for in-service examinations due to component configuration or physical barriers which would require a major modification to the existing hardware.

2

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS Table 1 - Unit 1 Summary of Class 1 Welds for Which Relief is Requested FLK Surge Nozzle to Lower Head / Due to nozzle On 004050 4-404 4.40" CC/S 66.4% configuration coverage of nozzle side base metal and Head weld was limited On PZR Spray Nozzle to Upper Head / Due to nozzle 004100 4-405 Head 4.40" CC/S 66.4% configuration coverage of nozzle side base metal and weld was limited Safety & Relief "A" Nozzle to PZR Upper Head / Due to nozzle configuration coverage of nozzle side base B3.110 004150 16-405A 96" 5" CC/S 36% metal and weld was limited. The nozzle enters the vessel at an angle thereby also limiting coverage attainable from the vessel side of the weld.

Safety & Relief "B" Nozzle to PZR Upper Head / Due to nozzle configuration coverage of nozzle side base 004200 16-405B 96" 5 CC/S 36% metal and weld was limited. The nozzle enters the B-D vessel at an angle thereby also limiting coverage

+ + F attainable from the vessel side of the weld.

+ + F SG Inlet Nozzle to Primary Head Nozzle / Machined 100805 SG- 1 -W5 42" 7.30" CC/S 84% transition on nozzle extension limited base metal coverage SG Inlet Nozzle to Primary Head Nozzle / Machined 106055 SG-12-W5 42" 7.30" CC/S 84% transition on nozzle extension limited base metal coverage B3.130 SG Outlet Nozzle to Primary Head Nozzle / Machined 100955 SG-11-W6 30" 5" CC/S 74.2% transition on nozzle extension limited base metal coverage SG Outlet Nozzle to Primary Head Nozzle / Machined 103205 SG- I1-W7 30" 5,1 CC/S 74.2% transition on nozzle extension limited base metal coverage RI.16 114900 12-SI-1010- 12" 1.20" 5/5 50% Pipe to Valve / Taper on Valve prevented any axial or R-A ] 7 10/12-SI-1009 12" 3.00" CC/S 43.7%

circumferential scanning from Valve side of the weld Angled branch connection 12" Pipe to 30" Pipe /. Weld location prevented any scanning from 12" pipe side.

3

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS 12-SI-1011- CASS/ Pipe to Safe End / No Code coverage was credited for 115950 12" 1.125" 50% scanning performed from Cast Stainless Steel Safe End side of weld.

Pipe to Tee / Scanning from Tee side of weld limited due to proximity of transition on Tee to the weld CC/S = Clad Carbon Steel S/S = Stainless Steel CASS = Cast Stainless Steel 4

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS B3.110 Pressurizer Nozzle-to-Vessel Welds, 4-404, 4-405, 16-405A, and 16-405B; The pressurizer nozzle-to-vessel head welds are accessible only from the head side based on the nozzle curvature. The scanning surface of the nozzle is essentially perpendicular to the head surface which prohibits the ultrasonic wave entering the Code required examination volume at an angle that will interrogate the weld volume for in-service flaws. The nondestructive examination (NDE) techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

B3.130 Steam Generator Nozzle-to-Vessel Welds, SG-11-W5, SG-12-W5, SG-11-W6 and SG-1 1-W7 The steam generator nozzle-to-vessel head welds are accessible only from the head side based on the designed nozzle configuration. The proximity of the nozzle radius prevented full examination coverage from the nozzle side. Scanning was performed from the nozzle; however, the ultrasonic waves did not cover the Code required examination volume at an angle that will interrogate the weld volume for in-service flaws. The NDE techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

R1.16 Circumferential Pipe Weld, 12-SI- 1010-7; and R1.20 Circumferential Pipe Welds, 10/12-SI- 1009, 12-SI- 10 11- 12, and 4-SR- 1006-4 The ultrasonic examination of the above pipe welds was limited in coverage due to component configuration (weld location relative to scanning surface, curvature/taper) and/or immovable penetrations and/or attachments. For these welds obtaining full coverage from both sides of the weld was not attainable since one side of the weld was not optimally oriented for scanning of the weld and adjacent base metal based on the surface angle of the component; therefore, the welds received a single-sided examination or partial two-sided 'examination resulting in less than 90% coverage of the required examination volume. The percentage of coverage reported represents the aggregate coverage from all examination angles and scans performed on the weld and adjacent base material.

The NDE techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

5. Burden Caused by Compliance In order to scan all of the required volume for these welds, the components would have to be redesigned to allow scanning from both sides of the weld, which is impractical. There were no recordable indications (other than geometric indications) found during the inspection of these welds.

Based on the components' designed configuration, the available coverage will not meet the requirements of the ASME Code, Code Case N-578 or Code Case N-460.

In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested for the components listed in Table 1 on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and the limitations imposed by design, geometry, and materials of construction.

Calvert Cliffs utilized examination techniques qualified to meet the requirements of ASME Section XI, Appendix VIII, as required in 10 CFR 50.55a(g)(6)(a)(c), that achieved the maximum practical amount of coverage obtainable within the limitations imposed by the design of the components and examination techniques. Additionally, VT-2 examinations are performed on the subject components of the reactor coolant pressure boundary during system pressure tests on a refueling outage frequency. Those examinations were completed during each refueling outage and no evidence of leakage was identified for these components.

5

ATTACHMENT (1)

RELIEF REQUEST ISI-24 FOR CCNPP UNIT 1 CLASS 1 COMPONENTS Further, the mandated requirement in 10 CFR 50.55a(b)(2)(xv)(A)(2), which states, "Where examination from both sides is not possible on austenitic welds or dissimilar metal 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." The Appendix VIII techniques applied at Calvert Cliffs, (PDI-UT-2) are not qualified for detection or length sizing of circumferentially oriented flaw indications when only single side access is available and the flaw is located on the far side of the weld, and therefore can't be credited for coverage although examinations were performed.

Based on the design configuration of the components and available examinations techniques, Calvert Cliffs was not able to achieve greater than 90% Code coverage of the required examination volume for the components listed above without major modifications to the components.

6. Proposed Alternative and Basis for Use No alternative examinations are planned for the welds during the current inspection interval. The use of radiography as an alternate volumetric examination for all the above listed components is not practical due to component thickness and geometric configurations. Other restrictions making radiography impractical are the physical barriers prohibiting access for placement of source, film, image quality indicator, etc.

Based on the above, with due consideration of the earlier plant design, the underlying objectives of the Code required volumetric examinations have been met. The examinations were completed to the extent practical and no unacceptable flaws were present. VT-2 examinations performed on the subject Class I components during system pressure testing each refueling outage provide continued assurance that the structural integrity of the subject components is maintained.

Ultrasonic examination of the welds was conducted using personnel qualified in accordance with ASME Section XI, Appendix VII of the 1998 Edition, no Addenda. Ultrasonic procedures complied with the requirements of ASME Section V, Article 4 of the 1998 Edition as amended by Section XI, Appendix I. IWB-2500, Table IWB-2500-1, Examination Category B-P System Leakage Tests and VT-2 visual examinations performed each refueling outage provide adequate assurance of pressure boundary integrity.

In addition to the above Code required examinations (volumetric and pressure test), there are other activities which provide a high level of confidence that, in the unlikely event that leakage did occur through a weld it would be detected and proper action taken. Specifically, system leak rate limitations imposed by Technical Specifications, "Reactor Coolant System Operational Leakage,"

(LCO 3.4.13) as well as containment normal sump rate monitoring, provide additional assurance that any leakage would be detected prior to gross failure of the component. The component welds were inspected by volumetric and surface NDE methods during construction and verified to be free from unacceptable fabrication defects.

Therefore, reasonable assurance of quality and safety is based on the achieved coverage and results of the volumetric and/or surface and the pressure testing VT-2 examinations performed.

7. Duration of Proposed Alternative Relief is requested for the Third Ten-year Interval of the Inservice Inspection Program for Calvert Cliffs which was effective from July 1, 1999, and ended on June 30, 2009 for Unit 1.

6

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS Calvert Cliffs Nuclear Power Plant, LLC June 30, 2010

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS

1. ASME Code Component(s) Affected ASME Code Class 2 Examination Categories; C-A, C-B and R-A Item Numbers: C1.10, C2.21, RI.1 1 and R1.20

2. Applicable Code Edition and Addenda

American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section XI, 1998 Edition, no Addenda.

3. Applicable Code Requirement

American Society of Mechanical Engineers Code,Section XI, Sub-article IWC-2500 states in part, "Components shall be examined and tested as specified in Table IWC-2500-l." Table IWC-2500-1 requires an examination of applicable Class 2 pressure retaining-welds, which includes essentially 100% of weld length once during the ten-year interval for Code Categories C-A, Item Number C 1.10 and C-B, Item Number C2.21.

A risk-informed in-service inspection (RI-ISI) program was approved for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs) by the Nuclear Regulatory Commission (NRC) on April 16, 2003. The RI-ISI was developed for Class 1 and 2 piping welds for the Examination Category B-F, B-J, C-F-i, and C-F-2 circumferential piping welds in a manner consistent with ASME Code,Section XI, Code Case N-578. Code Case N-578 examination requirements are listed in Table I, Examination Category R-A, Item No. R1.1 1 (TASCS), R1.16 (IGSCC), and R1.20 (No Degradation Mechanism);

and require essentially 100% of the required volume of the weld and adjacent base material to be examined.

Code Case N-460 permits a reduction in examination coverage of Class I and Class 2 welds provided the coverage reduction is less than 10%. Calvert Cliffs has adopted Code Case N-460 in the Inservice Inspection (ISI) Program Plan, as permitted by NRC Regulatory Guide 1.147, Revision 15.

4. Impracticality of Compliance Title 10 CFR 50.55a recognizes the limitations to in-service inspection of components in accordance with Section XI of the ASME Code that are imposed due to early plants design and construction, as follows: 10 CFR 50.55a(g)(1), "For a boiling or pressurized water-cooled nuclear power facility whose construction permit was issued prior to January 1, 1971, components (including supports) must meet the requirements of paragraphs (g)(4) and (g)(5) of this section to the extent practical,"

Title 10 CFR 50.55a(g)(4) states, "Throughout the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports) which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements, except design and access provisions and pre-service examination requirements, set forth in Section XI of Editions of the ASME Boiler and Pressure Vessel Code ... to the extent practical within the limitations of design, geometry and materials of construction of the components."

Further, 10 CFR 50.55a(g)(5)(iii) states that, "If the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in § 50.4, information to support the determinations."

I

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS Calvert Cliffs has determined that the following welds (shown in Table 1 below) were limited from achieving greater than 90% of the required examination volume for in-service examinations due to component configuration or physical barriers which would require a major modification to the existing hardware.

2

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS Table 1- Unit 1 Summary of Class 2 Welds for Which Relief is Requested Channel Barrel-to-Flange / Close proximity of Flange 252000 SCHE-1 1-1 45" 1.25" CC/S 71.8% transition to the weld limits attaining full coverage from the C-A C1.10 flange side of weld Channel Barrel-to-Flange / Close proximity of Flange 252350 SCHE-12-2 45" 1.25" CC/S 79.6% transition to the weld limits attaining full coverage from the flange side of weld 252450 SCHE 10" 1.125" S/S to 51.9% Outlet Nozzle to Shell / Due to nozzle configuration C-B C2.21 N2 CC/S coverage of the nozzle side base metal and weld was limited 252100 SCHE 10" 1.125" S/S to 44.5% Inlet Nozzle to Shell / Due to nozzle configuration coverage N 1 CC/S of the nozzle side base metal and weld was limited RI l1 417150 12-SC- 12" 0.33" S/S 84% Pipe to Tee / Coverage limited by intrados of adjacent Tee-1215-18 connection 14-SI-1201- 025" S/S 50% Valve to Elbow / Due to taper on valve body no coverage 1 was attainable from valve side of weld.

312250 12-SI-1216- 12" 0.25" S/S 75% Tee to Pipe / Coverage limited by close proximity of 1 intrados of Tee 12-SI-1214- S/S to Pipe to Tee / No Code coverage was credited for scanning 310050 312" 0.28" CASS 50% performed from Cast Stainless Steel Side of weld 12-SM-1214- S/S to 50% Pipe to Tee / No Code coverage was credited for scanning R-A 5 CASS performed from Cast Stainless Steel Side of weld R1.20 310650 12-SI-1214- 025" S/S 50/ Elbow to Valve / Due to taper on valve body no coverage 3 12 12" 0 was attainable from valve side of weld Valve to Pipe / Due to taper on valve body no coverage was 0 2attainable from valve side of weld Branch to Elbow / Due to taper on Branch Connection 338850 4-SI-1209-1 4" 0.38" S/S 50% (nozzle) no coverage was attainable from Branch side of weld 417200 10-SC- 10" 0.25" S/S 74.5% Tee to Pipe / Integral attachments on pipe side of weld in 12 14-1 close proximity to weld obstructed transducer 3

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS Table 1- Unit 1 Summary of Class 2 Welds for Which Relief is Requested 2Cat CHEp-ID Stem 11-1 Iia 45" 1.k I C/atS C7.era ns it t on wea ttainfor C fvullge coeagetfo mt

~No. 2 Channel Barrel-to-Flange / Close proximity of Flange 252000 SCHE-1 1-1 45" 1.25" CC/S 71.8% transition to the weld limits attaining full coverage from the C-A CLIO0 flange side of weld Channel Barrel-to-Flange / Close proximity of Flange 252350 SCH-E-12-2 45" 1.25" Cc/S 79.6% transition to the weld limits attaining full coverage from the

______flange side of weld 252450 SCHE 10" 1.125" SiS to 51.9% Outlet Nozzle to Shell / Due to nozzle configuration N2 CC/S coverage of the nozzle side base metal and weld was limited 252100 SCHE 10" 1.125" S/S to 44.5% Inlet Nozzle to Shell / Due to nozzle configuration coverage NI CC/S of the nozzle side base metal and weld was limited RI.11 417150 12-SC-15-8 12" 0.33" S/S 84% cneto to Tee / Coverage limited by intrados of adjacent Tee-Pipe 1215-18 connection 307150 14-SI-1201- 14" 0.25" S/S 50% Valve to Elbow / Due to taper on valve body no coverage 1 was attainable from valve side of weld.

312250 12-SI-1216- 12" 0.25" S/S Tee to Pipe / Coverage limited by close proximity of 1 intrados of Tee 310050 12-SI-1214- 12" 0.28" S/S to 50% Pipe to Tee / No Code coverage was credited for scanning 3 CASS performed from Cast Stainless Steel Side of weld 12-SI-1214- S/S to 50% Pipe to Tee / No Code coverage was credited for scanning R-A 31020 5 CASS performed from Cast Stainless Steel Side of weld R1.20 310650 12-SI-1214- 12" 0.25" S/S 50% Elbow to Valve / Due to taper on valve body no coverage 12 was attainable from valve side of weld Valve to Pipe / Due to taper on valve body no coverage was attainable from valve side of weld Branch to Elbow / Due to taper on Branch Connection 338850 4-SI-1209-1 4" 0.38" S/S 50% (nozzle) no coverage was attainable from Branch side of weld 417200 10-SC- 10" 0.25" S/S 74.5% Tee to Pipe / Integral attachments on pipe side of weld in

__1214-1 _ close proximity to weld obstructed transducer 4

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS ItTh2 No-ag Noi Mat I'eeitonIRao or Co%kragechmtt 16050 12-SC- I I ,, 50% Valve to Tee / Due to taper on valve body no coverage was 4 1213-1 10" 0.33 attainable from valve side of weld CC/S = Clad Carbon Steel S/S = Stainless Steel CASS = Cast Stainless Steel 5

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS C1.10 Shell-to-Flange Circumferential Weld, #11 and #12 Shutdown Cooling Heat Exchangers

- SCHE-1 1-1 and SCHE-12-2 The ultrasonic interrogation of the channel shell to flange weld could only be partially obtained from flange side due to the component configuration and close proximity of the weld to the flange transition. The nondestructive examination (NDE) techniques and procedures used incorporated similar examination techniques qualified under Appendix VIII of the ASME Section XI Code.

C2.21 Nozzle-to-Shell Welds, #11 and #12 Shutdown Cooling Heat Exchangers - SCHE-1 I-NI and SCHE-12-N2 The nozzle-to-shell weld is primarily accessible from the shell side based on the component configuration. The nozzle scanning surface is essentially perpendicular to the shell which prohibits the ultrasonic wave entering the Code required examination volume at an angle that will interrogate the weld volume for in-service flaws. The NDE techniques and procedures used incorporated similar examination techniques qualified under Appendix VIII of the ASME Section XI Code.

R1.11 Circumferential Pipe Welds, 12-SC- 1215-18; and R1.20 Circumferential Pipe Welds, 14-SI-1201-1, 12-SI-1216-1, 12-SI-1214-3, 12-SI-1214-5, 12-SI-1214-12, 4-SI-1206-7, 4-SI-1209-I, 10-SC-1214-1 and 12-SC-1213-1 The ultrasonic examination of the above pipe welds was limited in coverage due to component configuration (weld location relative to scanning surface, curvature/taper) and/or immovable penetrations and/or attachments. For these welds obtaining full coverage from both sides of the weld was not attainable since one side of the weld was not optimally oriented for scanning of the weld and adjacent base metal based on the surface angle of the component; therefore, the welds received a single-sided examination or partial two-sided examination resulting in less than 90% coverage of the required examination volume. The percentage of coverage reported represents the aggregate coverage from all examination angles and scans performed on the weld and adjacent base material.

The NDE techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

5. Burden Caused by Compliance In order to scan all of the required volume for these welds, the components would have to be redesigned to allow scanning from both sides of the weld, which is impractical. There were no recordable indications (other than geometric indications) found during the inspection of these welds.

Based on the components designed configuration, the available coverage will not meet the requirements of the ASME Code, Code Case N-578 or Code Case N-460.

In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested for the components listed in Table 1 on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and the limitations imposed by design, geometry, and materials of construction.

Calvert Cliffs utilized examination techniques qualified to meet the requirements of ASME Section XI, Appendix VIII, as required in 10 CFR 50.55a(g)(6)(a)(c), that achieved the maximum practical amount of coverage obtainable within the limitations imposed by the design of the components and examination techniques. Additionally, VT-2 examinations are performed on the subject components of the reactor coolant pressure boundary during system pressure tests on a refueling outage frequency. Those examinations were completed during each refueling outage and no evidence of leakage was identified for these components.

6

ATTACHMENT (2)

RELIEF REQUEST ISI-25 FOR CCNPP UNIT 1 CLASS 2 COMPONENTS Further, the mandated requirement in 10 CFR 50.55a(b)(2)(xv)(A)(2), which states, "Where examination from both sides is not possible on austenitic welds or dissimilar metal 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." The Appendix VIII techniques applied at Calvert Cliffs, (PDI-UT-2) are not qualified for detection or length sizing of circumferentially oriented flaw indications when only single side access is available and the flaw is located on the far side of the weld, and therefore can't be credited for coverage although examinations were performed.

Based on the design configuration of the components and available examinations techniques, Calvert Cliffs was not able to achieve greater than 90% Code coverage of the required examination volume for the components listed above without major modifications to the components.

6. Proposed Alternative and Basis for Use No alternative examinations are planned for the welds during the current inspection interval. The use of radiography as an alternate volumetric examination for all the above listed components is not practical due to component thickness and geometric configurations. Other restrictions making radiography impractical are the physical barriers prohibiting access for placement of source, film, image quality indicator, etc.

Based on the above, with due consideration of the earlier plant design, the underlying objectives of the Code required volumetric examinations have been met. The examinations were completed to the extent practical and no unacceptable flaws were present. VT-2 examinations performed on the subject Class 2 components during system pressure testing each refueling outage provide continued assurance that the structural integrity of the subject components is maintained.

Ultrasonic examination of the welds was conducted using personnel qualified in accordance with ASME SectionXI, Appendix VII of the 1998 Edition, no Addenda. Ultrasonic procedures complied with the requirements of ASME Section V, Article 4 of the 1998 Edition as amended by Section XI, Appendix I. IWC-2500, Table IWC-2500-1, Examination Category C-H System Leakage Tests and VT-2 visual examinations performed each refueling outage provide adequate assurance of pressure boundary integrity.

In addition to the above Code required examinations (volumetric and pressure test), there are other activities which provide a high level of confidence that, in the unlikely event that leakage did occur through a weld it would be detected and proper action taken. Specifically, system leak rate limitations imposed by Technical Specifications, "Reactor Coolant System Operational Leakage,"

(LCO 3.4.13) as well as containment normal sump rate monitoring, provide additional assurance that any leakage would be detected prior to gross failure of the component. The component welds were inspected by volumetric and surface NDE methods during construction and verified to be free from unacceptable fabrication defects.

Therefore, reasonable assurance of quality and safety is based on the achieved coverage and results of the volumetric and/or surface and the pressure testing VT-2 examinations performed.

7. Duration of Proposed Alternative Relief is requested for the Third Ten-Year Interval of the Inservice Inspection Program for Calvert Cliffs which was effective from July 1, 1999, and ended on June 30, 2009 for Unit 1.

7

ATTACHMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UNIT 2 CLASS 1 COMPONENTS Calvert Cliffs Nuclear Power Plant, LLC June 30, 2010

ATTACHMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UNIT 2 CLASS 1 COMPONENTS

1. ASME Code Component(s) Affected ASME Code Class I Examination Categories: B-D, and R-A Item Numbers: B3.1 10, RI.1 1 and R1.20

2. Applicable Code Edition and Addenda

American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section XI, 1998 Edition, no Addenda.

3. Applicable Code Requirement

American Society of Mechanical Engineers Code,Section XI, Sub-article IWB-2500 states in part, "Components shall be examined and tested as specified in Table IWB-2500-l." Table IWB-2500-1 requires an examination of applicable Class 1 pressure/retaining-welds, which includes essentially 100% of weld length once during the ten-year interval for Code Category B-D, Item Number B3.1 10.

A risk-informed in-service inspection (RI-ISI) program was approved for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs) by the NRC on April 16, 2003. The RI-ISI was developed for Class 1 and 2 piping welds for the Examination Category B-F, B-J, C-F-I, and C-F-2 circumferential piping welds in a manner consistent with ASME Code,Section XI, Code Case N-578. Code Case N-578 examination requirements are listed in Table I, Examination Category R-A, Item No. RI.11 (TASCS), R1.16 (IGSCC), and R1.20 (No Degradation Mechanism), and require essentially 100% of the required volume of the weld and adjacent base material to be examined.

Code Case N-460 permits a reduction in examination coverage of Class I and Class 2 welds provided the coverage reduction is less than 10%. Calvert Cliffs has adopted Code Case N-460 in the Inservice Inspection (ISI) Program Plan, as permitted by NRC Regulatory Guide 1.147, Revision 15.

4. Impracticality of Compliance Title 10 CFR 50.55a recognizes the limitations to in-service inspection of components in accordance with Section XI of the ASME Code that are imposed due to early plant design and construction, as follows: 10 CFR 50.55a(g)(1), "For a boiling or pressurized water-cooled nuclear power facility whose construction permit was issued prior to January 1, 1971, components (including supports) must meet the requirements of paragraphs (g)(4) and (g)(5) of this section to the extent practical,"

Title 10 CFR 50.55a(g)(4) states, "Throughout the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports) which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements, except design and access provisions and pre-service examination requirements, set forth in Section XI of editions of the ASME Boiler and Pressure Vessel Code ... to the extent practical within the limitations of design, geometry and materials of construction of the components."

Further, 10 CFR 50.55a(g)(5)(iii) states that, "If the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in § 50.4, information to support the determinations."

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ATTACHMENT (3)

RELIEF REQUEST ISI-26 FoR CCNPP UNIT 2 CLASS 1 COMPONENTS Calvert Cliffs has determined that the following welds (shown in Table I below) were limited from achieving greater than 90% of the required examination volume for in-service examinations due to component configuration or physical barriers which would require a major modification to the existing hardware.

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ATTACHIMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UTNIT 2 CLASS 1 COMPONENTS Table 1 - Unit 2 Summary of Class 1 Welds for Which Relief is Requested PZR Surge Nozzle to Lower Head / Due to nozzle On Lower configuration coverage of nozzle side base metal 103080 4-404 4.4" CC/S 69.5%

Head and weld was limited PZR Spray Nozzle to Upper Head / Due to nozzle 103090 4-405 On Upper 4.4" CC/S 70% configuration coverage of nozzle side base metal and weld was limited Safety & Relief "A" Nozzle to Upper Head / Due to B-D B3.1 10 nozzle configuration coverage of nozzle side base 103100 16-405A 96" 5.0" CC/S 41% metal and weld was limited. The nozzle enters the vessel at an angle thereby also limiting coverage attainable from the vessel side of the weld.

Safety & Relief "B" Nozzle to Upper Head / Due to nozzle configuration coverage of nozzle side base 103110 16-405B 96" 5.0" CC/S 42% metal and weld was limited. The nozzle enters the vessel at an angle thereby also limiting coverage

+ + 4- 4 4 4 attainable from the vessel side of the weld.

Pipe to Branch Connection / Coverage of weld from 30-RC-21A-109360 8.0" 3.0" CC/S 75% Branch (nozzle) Penetration side of weld limited due 10/2-CV-2005 to configuration Tee to Pipe / Adjacent weld in close proximity on 136020 4-PS-2003-2 4.0" 0.44" S/S 37.5% pipe side limited coverage to Tee side which was also limited by obstruction by a penetration in close proximity to the weld.

R-A RI.ll 136040 4-PS-2003-4 4.0" 0.44" S/S 50% Tee to PipenTesd atial / Due to fwl geometry no coverage was attainable on Tee side of weld 138470 3-PS-2002-27 3.0" 0.41", 5/5 50% Valve to Pipe / Due to taper on valve body no coverage was attainable from valve side of weld Elbow to Pipe / Adjacent weld in close proximity to examined weld limited coverage which was also 143030 2.5-SR-2003-4 2.5" 0.38" S/S 43%

limited at Intrados of Elbow being in close proximity to the weld.

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ATTACHMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UNIT 2 CLASS 1 COMPONENTS S/S Elbow to Safe End / No Code coverage was credited 12-SI-2010 - to 116180 12" 1.13" 50% for scanning performed from Cast Stainless Steel 12 CAS Safe End side of weld S

Elbow to Safe End / No Code coverage was credited 117110 12-SI-2011 - 12" 1.13" to 50% for scanning performed from Cast Stainless Steel 12 CAS Safe End side of weld S

1S2 -Pipe to Safe End / No Code coverage was credited R1.20 118110 12-S2012 - 12" 1.16" CA 50% for scanning performed from Cast Stainless Steel Safe End side of weld S

Tee to Pipe / No examination could be performed from Tee side of weld due to Weld crown configuration. This also limited coverage from the pipe side of weld Safe-end to Elbow / Due to geometry no coverage was attainable on Safe End side of weld due to taper 141010 4-SR-2005-2 4.0" 0.41" S/S 36.7%

and lift-off at weld toe also limited coverage from elbow side of weld CC/S - Clad Carbon Steel S/S = Stainless Steel CASS = Cast Stainless Steel 4

ATTACHMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UNIT 2 CLASS 1 COMPONENTS B3.110 Pressurizer Nozzle-to-Vessel Welds, 4-404, 4-405, 16-405A, and 16-405B; The pressure nozzle-to-vessel head welds are accessible only from the head side based on the nozzle curvature. The scanning surface of the nozzle is essentially perpendicular to the head surface which prohibits the ultrasonic wave entering the Code required examination volume at an angle that will interrogate the weld volume for in-service flaws. The nondestructive examination (NDE) techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

RI.11 Circumferential Pipe Welds, 30-RC-21A-10/2-CV-2005, 4-PS-2003-2, 4-PS-2003-4, 3-PS-2002-27 and 2.5-SR-2003-4, and; R1.20 Circumferential Pipe Welds, 12-SI-2010-12, 12-SI-2011-12, 12-SI-2012-12, 4-SR-2001-1, and 4-SR-2005-2 The ultrasonic examination of the above pipe welds was limited in coverage due to component configuration (weld location relative to scanning surface, curvature/taper) and/or immovable penetrations and/or attachments. For these welds obtaining full coverage from both sides of the weld was not attainable since one side of the weld was not optimally oriented for scanning of the weld and adjacent base metal based on the surface angle of the component; therefore, the welds received a single-sided examination or partial two-sided examination resulting in less than 90% coverage of the required examination volume. The percentage of coverage reported represents the aggregate coverage from all examination angles and scans performed on the weld and adjacent base material.

The NDE techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

5. Burden Caused by Compliance In order to scan all of the required volume for these welds, the components would have to be redesigned to allow scanning from both sides of the weld, which is impractical. There were no recordable indications (other than geometric indications) found during the inspection of these welds.

Based on the components designed configuration, the available coverage will not meet the requirements of the ASME Code, Code Case N-578 or Code Case N-460.

In accordance with 10 CFR 50.5 5a(g)(5)(iii), relief is requested for the components listed in Table I on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and the limitations imposed by design, geometry, and materials of construction.

Calvert Cliffs utilized examination techniques qualified to meet the requirements of ASME Section XI, Appendix VIII, as required in 10 CFR 50.55a(g)(6)(a)(c), that achieved the maximum practical amount of coverage obtainable within the limitations imposed by the design of the components and examination techniques. Additionally, VT-2 examinations are performed on the subject components of the reactor coolant pressure boundary during system pressure tests on a refueling outage frequency. Those examinations were completed during each refueling outage and no evidence of leakage was identified for these components.

Further, the mandated requirement in 10 CFR 50.55a(b)(2)(xv)(A)(2), which states, "Where examination from both sides is not possible on austenitic welds or dissimilar metal 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." The Appendix VIII techniques applied at Calvert Cliffs, (PDI-UT-2) are not qualified for detection or length sizing of circumferentially oriented flaw indications when only single side access is available and the flaw is located on the far side of the weld, and therefore can't be credited for coverage although examinations were performed.

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ATTACHMENT (3)

RELIEF REQUEST ISI-26 FOR CCNPP UNIT 2 CLASS 1 COMPONENTS Based on the design configuration of the components and available examinations techniques, Calvert Cliffs was not able to achieve greater than 90% Code coverage of the required examination volume for the components listed above without major modifications to the components.

6. Proposed Alternative and Basis for Use No alternative examinations are planned for the welds during the current inspection interval. The use of radiography as an alternate volumetric examination for all the above listed components is not practical due to component thickness and geometric configurations. Other restrictions making radiography impractical are the physical barriers prohibiting access for placement of source, film, image quality indicator, etc.

Based on the above, with due consideration of the earlier plant design, the underlying objectives of the Code requiredvolumetric examinations have been met. The examinations were completed to the extent practical and no unacceptable flaws were present. VT-2 examinations performed on the subject Class 1 components during system pressure testing each refueling outage provide continued assurance that the structural integrity of the subject components is maintained.

Ultrasonic examination of the welds was conducted using personnel qualified in accordance with ASME Section XI, Appendix VII of the 1998 Edition, no Addenda. Ultrasonic procedures complied with the requirements of ASME Section V, Article 4 of the 1998 Edition as amended by Section XI, Appendix I. IWB-2500, Table IWB-2500-1, Examination Category B-P System Leakage Tests and VT-2 visual examinations performed each refueling outage provide adequate assurance of pressure boundary integrity.

In addition to the above Code required examinations (volumetric and pressure test), there are other activities which provide a high level of confidence that, in the unlikely event that leakage did occur through a weld it would be detected and proper action taken. Specifically, system leak rate limitations imposed by Technical Specifications, "Reactor Coolant System Operational Leakage,"

(LCO 3.4.13) as well as containment normal sump rate monitoring, provide additional assurance that any leakage would be detected prior to gross failure of the component. The component welds were inspected by volumetric and surface NDE methods during construction and verified to be free from unacceptable fabrication defects.

Therefore, reasonable assurance of quality and safety is based on the achieved coverage and results of the volumetric and/or surface and the pressure testing VT-2 examinations performed.

7. Duration of Proposed Alternative Relief is requested for the Third Ten-Year Interval of the Inservice Inspection Program for Calvert Cliffs which was effective from July 1, 1999, and ended on June 30, 2009 for Unit 2.

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ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS Calvert Cliffs Nuclear Power Plant, LLC N June 30, 2010

ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS

1. ASME Code Component(s) Affected ASME Code Class 2 Examination Categories: C-A, C-B and R-A Item Numbers: CI. 10, C2.21 and R1.20

2. Applicable Code Edition and Addenda

American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code,Section XI, 1998 Edition, no Addenda.

3. Applicable Code Requirement

American Society of Mechanical Engineers Code,Section XI, Sub-article IWC-2500 states in part, "Components shall be examined and tested as specified in Table IWC-2500-1." Table IWC-2500-1 requires an examination of applicable Class 2 pressure retaining-welds, which includes essentially 100% of weld length once during the ten-year interval for Code Categories C-A, Item Number C 1.10 and C-B, Item Number C2.2 1.

A risk-informed in-service inspection (RI-ISI) program was approved for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs) by the NRC on April 16, 2003. The RI-ISI was developed for Class 1 and 2 piping welds for the Examination Category B-F, B-J, C-F-I, and C-F-2 circumferential piping welds in a manner consistent with ASME Code,Section XI, Code Case N-578. Code Case N-578 examination requirements are listed in Table I, Examination Category R-A, Item No. RI.11 (TASCS), R1.16 (IGSCC), and R1.20 (No Degradation Mechanism), and require essentially 100% of the required volume of the weld and adjacent base material to be examined.

Code Case N-460 permits a reduction in examination coverage of Class I and Class 2 welds provided the coverage reduction is less than 10%. Calvert Cliffs has adopted Code Case N-460 in the Inservice Inspection.w (ISI) Program Plan, as permitted by NRC Regulatory Guide 1.147, Revision 15.

4. Impracticality of Compliance Title 10 CFR 50.55a recognizes the limitations to in-service inspection of components in accordance with Section XI of the ASME Code that are imposed due to early plant design and construction, as follows: 10 CFR 50.55a(g)(1), "For a boiling or pressurized water-cooled nuclear power facility whose construction permit was issued prior to January 1, 1971, components (including supports) must meet the requirements of paragraphs (g)(4) and (g)(5) of this section to the extent practical,"

Title 10 CFR 50.55a(g)(4) states, "Throughout the service life of a boiling or pressurized water-cooled nuclear power facility, components (including supports) which are classified as ASME Code Class 1, Class 2, and Class 3 must meet the requirements, except design and access provisions'and pre-service examination requirements, set forth in Section XI of Editions of the ASME Boiler and Pressure Vessel Code ... to the extent practical within the limitations of design, geometry and materials of construction of the components."

Further, 10 CFR 50.55a(g)(5)(iii) states that, "If the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in § 50.4, information to support the determinations."

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ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS Calvert Cliffs has determined that the following welds (shown in Table 1 below) were limited from achieving greater than 90% of the required examination volume for in-service examinations due to component configuration or physical barriers which would require a major modification to the existing hardware.

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ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS Table 1 - Unit 2 Summary of Class 2 Welds for Which Relief is Requested Channel l5arrel-to-1lange / Close proximity ot 201650 SCHE-22-1 45" 1.25" CC/S 61% Flange transition to the weld limits attaining full coverage from the flange side of weld C-A CI.1O I + 4 4 + -I-Channel Barrel-to-Flange / Close proximity of 201700 SCHE-22-2 45" 1.25" CC/S 82.6% Flange transition to. the weld limits attaining full coverage from the flange side of weld S/S Outlet Nozzle to Shell / Due to nozzle configuration 201500 SCHE-2 I-N2 10" 1.125" to 51.3% coverage of the nozzle side base metal and weld was CC/S limited C-B C2.21 S/S Inlet Nozzle to Shell / Due to nozzle configuration 201400 SCHE-21-N1 10" 1.125" to . 50% coverage of the nozzleside base metal and weld was CC/S limited 215100 10-SI-2002-3 10.0" 0.25" S/S 45.7% Pipe to Valve / Due. to taper on valve body no coverage was attainable from valve side of weld Flange to Expander/ Close proximity of Flange 215550 10-SI-2003-2 10.0" 0.38" S/S 50% transition to the weld limits attaining coverage from the flange side of weld R-A R1.20 Elbow to Reducer / Access to bottom of weld 225750 19 6.0" 0.43" S/S 78.7% obstructed by immovable structural member (I-beam)

.Elbow to Pipe / Integral welded attachment (saddle) 230650 6-SI-2017-11 6.0" 0.30" S/S 75% adjacent to weld prevented access to the lower 180 degrees of weld on pipe side of weld CC/S = Clad Carbon Steel S/S = Stainless Steel 3

ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNIPP UNIT 2 CLASS 2 COMPONENTS Table 1 - Unit 2 Summary of Class 2 Welds for Which Relief is Requested Channel Barrel-to-Flange / Close proximity of 201650 SCHE-22-1 45" 1.25" CC/S 61% Flange transition to the weld limits attaining full coverage from the flange side of weld C-A C1.10 Channel Barrel-to-Flange / Close proximity of 201700 SCHE-22-2 45" 1.25" CC/S 82.6% Flange transition to the weld limits attaining full coverage from the flange side of weld S/S Outlet Nozzle to Shell / Due to nozzle configuration 201500 SCHE-21-N2 10" 1.125" to 51.3% coverage of the nozzle side base metal and weld was C-B C2.21 CC/S limited S/S Inlet Nozzle to Shell / Due to nozzle configuration 201400 SCHE-21-N1 10" 1.125" to 50% coverage of the nozzle side base metal and weld was CC/S limited 215100 10-SI-2002-3 10.0" 0.25" S/S 45.7% Pipe to Valve / Due to taper on valve body no coverage was attainable from valve side of weld Flange to Expander/ Close proximity of Flange 215550 10-SI-2003-2 10.0" 0.38" S/S 50% transition to the weld limits attaining coverage from the flange side of weld R-A R1.20 Elbow to Reducer / Access to bottom of weld 225750 6-SI-2004A- 6.0" 0.43" S/S 78.7% obstructed by immovable structural member (I-19 beam)

Elbow to Pipe / Integral welded attachment (saddle) 230650 6-SI-2017-11 6.0" 0.30" S/S 75% adjacent to weld prevented access to the lower 180 degrees of weld on pipe side of weld CC/S = Clad Carbon Steel S/S = Stainless Steel 4

ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS CI.1O Shell-to-Flange Circumferential Welds, #22 Shutdown Cooling Heat Exchanger -

SCHE-22-1 and SCHE-22-2 The ultrasonic interrogation of the channel shell to flange weld could only be partially obtained fro'm flange side due to the component configuration and close proximity of the weld to the flange transition. The nondestructive examination (NDE) techniques and procedures used incorporated similar examination techniques qualified under Appendix VIII of the ASME Section XI Code.

C2.21 Nozzle-to-Shell Welds, #21 Shutdown Cooling Heat Exchanger - SCHE-21-NI and SCHE-2 1-N2 The nozzle-to-shell weld is primarily accessible from the shell side based on the component configuration. The nozzle scanning surface is essentially perpendicular to the shell which prohibits the ultrasonic wave entering the Code required, examination volume at an angle that will interrogate the weld volume for in-service flaws. The NDE te'chniques and procedures used incorporated similar examination techniques qualified under Appendix VIII of the ASME Section XI Code.

R1.20 Circumferential Pipe Welds, 10-SI-2002-3, 10-SI-2003-2, 6-SI-2004A-19, and 6-SI-2017-11 The ultrasonic examination of the above pipe welds was limited in coverage due to component configuration (weld location relative to scanning surface, curvature/taper) and/or immovable penetrations and/or attachments. For these welds obtaining full coverage from both sides of the weld was not attainable since one side of the weld was not optimally oriented for scanning of the weld and adjacent base metal based on the surface angle of the component;. therefore, the welds received a single-sided examination or partial two-sided examination resulting in less than 90% coverage of the required examination volume. The percentage of coverage reported represents the aggregate coverage from all examination angles and scans performed on the weld and adjacent base material.

The NDE techniques and procedures used incorporated examination techniques qualified under Appendix VIII of the ASME Section XI Code.

5. Burden Caused by Compliance In order to scan all of the required volume for these welds, the components would have to be redesigned to allow scanning from both sides of the weld, which is impractical. There were no recordable indications (other than geometric indications) found during the inspection of these welds.

Based on the components designed configuration, the available coverage will not meet the requirements of the ASME Code, Code Case N-578 or Code Case N-460.

In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested for the components listed in Table I on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and the limitations imposed by design, geometry, and materials of construction.

Calvert Cliffs utilized examination techniques qualified to meet the requirements of ASME Section XI, Appendix VIII, as required in 10 CFR 50.55a(g)(6)(a)(c), that achieved the maximum practical amount of coverage obtainable within the limitations imposed by the design of the components and examination techniques. Additionally, VT-2 examinations are performed on the subject components of the reactor coolant pressure boundary during system pressure tests on a refueling outage frequency. Those examinations were completed during each refueling outage and no evidence of leakage was identified for these components.

Further, the mandated requirement in 10 CFR 50.55a(b)(2)(xv)(A)(2), which states, "Where examination from both sides is not possible on austenitic welds or dissimilar metal welds, full 5

p ATTACHMENT (4)

RELIEF REQUEST ISI-27 FOR CCNPP UNIT 2 CLASS 2 COMPONENTS 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." The Appendix VIII techniques applied at Calvert Cliffs, (PDI-UT-2) are not qualified for detection or length sizing of circumferentially oriented flaw indications when only single side access is available and the flaw is located on the far side of the weld, and therefore can't be credited for coverage although examinations were performed.

Based on the design configuration of the components and available examinations techniques, Calvert Cliffs was not able to achieve greater than 90% Code coverage of the required examination volume for the components listed above without major modifications to the components.

6. Proposed Alternative and Basis for Use No alternative examinations are planned for the welds during the current inspection interval. The use of radiography as an alternate volumetric examination for all the above listed components is not practical due to component thickness and geometric configurations. Other restrictions making radiography impractical are the physical barriers prohibiting access for placement of source, film, image quality indicator, etc.

Based on the above, with due consideration of the earlier plant design, the underlying objectives of the Code required volumetric examinations have been met. The examinations were completed to the extent practical and no unacceptable flaws were present. VT-2 examinations performed on the subject Class 2 components during system pressure testing each refueling outage provide continued assurance that the structural integrity of the subject components is maintained.

Ultrasonic examination of the welds was conducted using personnel qualified in accordance with ASME Section XI, Appendix VII of the 1998 Edition, no Addenda. Ultrasonic procedures complied with the requirements of ASME Section V, Article 4 of the 1998 Edition as amended by Section XI, Appendix I. IWC-2500, Table IWC-2500-1, Examination Category C-H System Leakage Tests and VT-2 visual examinations performed each refueling outage provide adequate assurance of pressure boundary integrity.

In addition to the above Code required examinations (volumetric and pressure test), there are other activities which provide a high level of confidence that, in the unlikely event that leakage did occur through a weld it would be detected and proper action taken. Specifically, system leak rate limitations imposed by Technical Specifications, "Reactor Coolant System Operational Leakage,"

(LCO 3.4.13) as well as containment normal sump rate monitoring, provide additional assurance that any leakage would be detected prior to gross failure of the component. The component welds were inspected by volumetric and surface NDE methods during construction and verified to be free from unacceptable fabrication defects.

Therefore, reasonable assurance of quality and safety is based on the achieved coverage and results of the volumetric and/or surface and the pressure testing VT-2 examinations performed.

7. Duration of Proposed Alternative Relief is requested for the Third Ten-year Interval of the Inservice Inspection Program for Calvert Cliffs which was effective from July 1, 1999, ended on June 30, 2009 for Unit 2.

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