Text

Relief Requests for Dissimilar Metal Butt Welds Baseline Inspections (RR-ISI-04-06 & ISI-04-07)
	ML12009A073
Person / Time
Site:	Calvert Cliffs
Issue date:	12/29/2011
From:	John Stanley; Constellation Energy Nuclear Group
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	ISI-04-07, RR-ISI-04-06
	Download: ML12009A073 (86)
	v • d • e

Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, Maryland 20657 CENG a joint venture of Corelliaton *flin Energy ,0 v.

CALVERT CLIFFS NUCLEAR POWER PLANT December 29, 2011 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION: Document Control Desk

SUBJECT:

Calvert Cliffs Nuclear Power Plant Unit Nos. I & 2; Docket Nos. 50-317 & 50-518 Relief Requests for Dissimilar Metal Butt Welds Baseline Inspections (RR-ISI-04-06 & ISI-04-07)

With the issuance of the revised 10 CFR 50.55a in July 2011, the Nuclear Regulatory Commission incorporated by reference American Society of Mechanical Engineers (ASME) Code Case N-770-1, "Alternative Examination Requirements and Acceptance Standards for Class I PWR Piping and Vessel Nozzle Butt Welds Fabricated with UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities,Section XI, Division I." Specific implementing requirements for ASME Code Case N-770-1 are documented in 10 CFR 50.55a(g)(6)(ii)(F)(2 thru 10). Calvert Cliffs Nuclear Power Plant, LLC (Calvert Cliffs) hereby requests Nuclear Regulatory Commission approval for use of alternative examination requirements to be applied for baseline examinations associated with dissimilar metal butt welds required by ASME Code Case N-770-1. Relief Request RR-ISI-04-06 addresses the applicable Unit 1 dissimilar metal butt welds and RR-ISI-04-07 addresses the applicable Unit 2 dissimilar metal butt welds. Use of these alternative examination requirements, as detailed in Attachments (1) and (2), maintain an acceptable level of quality and safety pursuant to 10 CFR 50.55a(a)(3)(i).

Because Item (3) of 10 CFR 50.55a(g)(6)(ii)(F) requires that all Inspection Items A-I, A-2, and B receive a baseline examination by the end of the first refueling outage after January 20, 2012, Calvert Cliffs requests approval of these alternative examination requirements be completed by February 15, 2012. This approval date supports unit startup following Unit l's 2012 Refueling Outage, which is scheduled to commence in February 2012 (the first outage after January 20, 2012). This relief request is effective for Calvert Cliffs Fourth Ten-Year Inservice Inspection Interval.

Document Control Desk December 29, 2011 Page 2 Should you have questions regarding this matter, please contact Mr. Douglas E. Lauver at (410) 495-5219.

ry yours, James J. Stanley Manager - Engineering Services JJS/KLG/bjd Attachments: (1) Relief Request for Calvert Cliffs Unit 1 Dissimilar Metal Butt Weld Examinations (RR-ISI-04-06)

Enclosure:

1. Unit I Examination Coverage Plots (2) Relief Request for Calvert Cliffs Unit 2 Dissimilar Metal Butt Weld Examinations (RR-ISI-04-07)

Enclosure:

1. Unit 2 Examination Coverage Plots cc: D. V. Pickett, NRC Resident Inspector, NRC W. M. Dean, NRC S. Gray, DNR

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

Calvert Cliffs Nuclear Power Plant, LLC December 29, 2011

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

1. ASME Code Component(s) Affected Code Class 1 PWR Pressure Retaining Dissimilar Metal Piping and Vessel Nozzle Butt Welds Containing Alloy 82/182. American Society of Mechanical Engineers (ASME) Code Case N-770-1, Table 1, Examinations Categories, Inspection Item B - Unmitigated butt weld at cold leg operating temperature, Inspection Item D - Uncracked butt weld mitigated with stress improvement, Inspection Item E - Cracked butt weld mitigated with stress improvement.

2. Applicable Code Edition and Addenda ASME Boiler and Pressure Vessel Code,Section XI, 2004 Edition, no Addenda - Code Case N-770-1 subject to conditions specified in 10 CFR 50.55a(g)(6)(ii)(F)(2 through 10).

3. Applicable Code Requirement With the issuance of a revised 10 CFR 50.55a in July 2011, the Nuclear Regulatory Commission (NRC) incorporated by reference ASME Code Case N-770-1, "Alternative Examination Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds Fabricated with UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities,Section XI, Division 1" (ASME Approval Date: December 25, 2009).

Specific implementing requirements are documented in 10 CFR 50.55a(g)(6)(ii)(F) and are listed below.

(1) Licensees of existing, operating pressurized-water reactors as of July 21, 2011 shall implement the requirements of ASME Code Case N-770-1, subject to the conditions specified in paragraphs (g)(6)(ii)(F)(2) through (g)(6)(ii)(F)(10) of this section, by the first refueling outage after August 22, 2011.

(2) Full structural weld overlays authorized by the NRC staff may be categorized as Inspection Items C or F, as appropriate; welds that have been mitigated by the Mechanical Stress Improvement Process (MSIPTM) may be categorized as Inspection Items D or E, as appropriate, provided the criteria in Appendix I of the code case have been met; for Inservice Inspection (ISI) frequencies, all other butt welds that rely on Alloy 82/182 for structural integrity shall be categorized as Inspection Items A-1, A-2, or B until the NRC staff has reviewed the mitigation and authorized an alternative code case Inspection Item for the mitigated weld, or until an alternative code case Inspection Item is used based on conformance with an ASME mitigation code case endorsed in Regulatory Guide 1.147 with conditions, if applicable, and incorporated in this section.

(3) Baseline examinations for welds in ASME Code Case N-770-1, Table 1, Inspection Items A-I, A-2, and B, shall be completed by the end of the next refueling outage after January 20, 2012.

Previous examinations of these welds can be credited for baseline examinations if they were performed within the re-inspection period for the weld item in ASME Code Case N-770-1, Table 1 using Section XI, Appendix VIII requirements and met the Code required examination volume of essentially 100 percent. Other previous examinations that do not meet these requirements can be used to meet the baseline examination requirement, provided NRC approval of alternative inspection requirements in accordance with paragraphs (a)(3)(i) or (a)(3)(ii) of this section is granted prior to the end of the next refueling outage after January 20, 2012.

I

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

(4) The axial examination coverage requirements of -2500(c) may not be considered to be satisfied unless essentially 100 percent coverage is achieved.

Items (5) through (9) of 10 CFR 50.55a(g)(6)(ii)(F) address future inspections beyond the baseline examination and are therefore not discussed in this relief request. Item (10) of 10 CFR 50.55a(g)(6)(ii)(F) addresses a mitigation that Calvert Cliffs does not have and is therefore not discussed in this relief request.

4. Reason for Request The relevant conditions for this relief request are items (2) through (4) of 10 CFR 50,55a(g)(6)(ii)(F). These requirements are applicable to the welds listed in Table A below.

Item (2) addresses defining the appropriate Inspection Item. Item (3) addresses performing the required baseline examination for that Inspection Item, while item (4) addresses the required examination coverage.

Item (2) of 10 CFR 50.55a(g)(ii)(F) requires that welds that have been mitigated by the MSIPTM may be categorized as Inspection Items D or E, as appropriate, provided the criteria in Appendix I of the Code Case have been met.

Item (3) of 10 CFR 50.55a(g)(6)(ii)(F) requires that all Inspection Items A-i, A-2, and B receive a baseline examination by the end of the first refueling outage after January 20, 2012. This report evaluates each location based on the specific Inspection Item frequency and examination coverage.

Whereas MRP-139 and ASME Code Case N-770-1 made allowances for axial examination coverage of dissimilar metal (DM) welds, the NRC has stated in item (4) above that essentially 100 percent coverage is required. This applies to meeting the baseline requirements for Item (3) above.

5. Component/Weld Scope The welds shown in Table A below are the applicable welds 2 inch nominal pipe size and greater covered by the requirements contained in ASME Code Case N-770-1, Section -1000. These welds have been categorized in accordance with Table 1 from ASME Code Case N-770-1. The ASME Section XI examination volume coverage achieved during the 2010 outage is also included in Table A below.

Examination coverage plots are included in Enclosure 1 for those inspections for which essentially 100 percent coverage was unable to be obtained.

2

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

TARIE A. INIT 1 flM WWID POPTYIATT*N ASME ASME Inspection ASME Axial Circ MRP-139 MRP-139 Nozzle Item Section XI Scan Scan MRP-139 Axial Scan Circ Scan DM Weld Designator /

ID Location Size Category Coverage (%) (%) Coverage (%) (%) Notes 102300 / 30-RC-11A-7 llA RCP Inlet 30" B 52.50% 60 45 92.50% 100 85 1,5 102450 / 30-RC-11A-10 llA RCP Outlet 30" B 57.00% 68 46 88.50% 98 79 3,6,7 104550 / 30-RC-11B-7 11B RCP Inlet 30" B 57.00% 65 49 91.50% 100 83 1,5 104700 / 30-RC-11B-10 liB RCP Outlet 30" B 43.50% 53 34 88.50% 98 79 3,6,7 107450 / 30-RC-12A-7 12A RCP Inlet 30" B 57.50% 70 49 90.50% 100 81 1,5 107600/30-RC-12A-10 12ARCP Outlet 30" B 53.00% 63 43 90.50% 100 81 1,5 109600 / 30-RC-12B-7 12B RCP Inlet 30" B 53.50% 62 45 91.50% 100 83 1,5 109750 / 30-RC-12B-10 12B RCP Outlet 30" B 60.50% 71 50 91.50% 100 83 1,7 110450 / 12-PSL-1 PZR Surge @ PZR 12" D 50.50% 63 38 82.50% 100 65 1,5,8 PZR Surge @ RCS 111100 / 12-PSL-13 Hot Leg 12" E 59.00% 61 57 97.00% 100 94 1,4 Shutdown Cooling to 113150 / 12-SC-1004-1 RCS Hot Leg 12" D 70.50% 71 70 99.00% 100 98 1,4 Safety Injection to 114350 / 12-SI-1009-16 llA Cold Leg 12" B 57.00% 65 49 93.50% 100 87 1,5 Safety Injection to 115200 / 12-SI-1010-14 1iB Cold Leg 12" B 47.00% 62 32 86.50% 100 73 1,5 Safety Injection to 116000 / 12-SI-1011-13 12A Cold Leg 12" B 47.50% 62 33 85.00% 100 70 1,5 Safety Injection to 116750 / 12-SI-1012-13 12B Cold Leg 12" B 48.50% 61 36 83.50% 100 67 1,5 118500 / 4-PS-1003-6 PZR Spray 4" D 79.00% 100 58 83.50% 100 67 1,5 PZR Spray from 118550 / 3-PS-1001-1 l1A Cold Leg 3" B 100% 100 100 100% 100 100 1,2,8 PZR Spray from 120350 / 3-PS-1002-1 11B Cold Leg 3" B 100% 100 100 100% 100 100 1,2,8 123100/4-SR-1005-1 PZR Safety/Relief 4" D 100% 100 100 100% 100 100 1,2 3

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

TABLE A, UNIT 1 DM WELD POPULATION ASME ASME Inspection ASME Axial Circ MRP-139 MRP-139 DM Weld Designator / Nozzle Item Section XI Scan Scan MRP-139 Axial Scan Circ Scan ID Location Size Category Coverage (%) (%) Coverage (%) (%) Notes 123450 / 4-SR-1006-1 PZR Safety/Relief 4" E 100% 100 100 100% 100 100 1,2,8 12A Cold Leg 125050 / 2-LD-1004-1 Letdown 2" B 100% 100 100 100% 100 100 1,2 128900 /2-CV-1004-19 12B Charging Inlet 2" B 100% 100 100 100% 100 100 1,2 130450 /2-CV-1005-29 I1A Charging Inlet 2" B 100% 100 100 100% 100 100 1,2,8 131200 /2-DR-1003-1 I1A Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,2 131500 /2-DR-1004-1 lIB Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,5 132150 /2-DR-1006-1 12B Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,2 RCS 11 Hot Leg 132450 /2-DR-1007-1 Drain 2" E 100% 100 100 100% 100 100 1,2 Locations in Bold operate at Cold Leg temperature.

NOTES:

1. 100% of primary water stress corrosion cracking (PWSCC) susceptible material examination volume has been examined for circumferential flaws.

2. 100% of PWSCC susceptible material examination volume has been examined for axial flaws.

3. Essentially 100% of the PWSCC susceptible material examination volume has been examined for circumferential flaws.

4. Essentially 100% of the PWSCC susceptible material examination volume has been examined for axial flaws.

5. A portion of the susceptible material examination volume from the wetted surface received limited examination for axial flaws.

6. A portion of the susceptible material examination volume from the wetted surface received limited examination for circumferential flaws.

7. A portion of the susceptible examination volume material from the wetted surface through to non susceptible material received limited examination for axial flaws.

8. These components received specific surface contouring to improve coverage. Coverage indicated in table is based on final contouring.

General Note for Table A: MRP-139 coverage was calculated and is included in the table and on the coverage plots. This volume differs from ASME Code Case N-770-1 in that it excludes cast stainless steel material and extends the examination volume 1/4 inch beyond known susceptible material. This coverage is a direct measure of what amount of susceptible material coverage was achieved. The cast stainless steel material was examined using an ASME Section XI, Appendix VIII dissimilar metal weld qualified procedure.

4

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

6. Burden Caused by Compliance 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), that achieved the maximum practical amount of coverage obtainable within the limitations imposed by the design of the components and examination techniques listed. Additionally, visual test for leakage (VE examinations in accordance with ASME Code Case N-722) were performed on the subject components of the reactor coolant pressure boundary during the 2010 refueling outage. Those examinations identified no evidence of leakage for these components. The combination of these examinations provides confidence that an acceptable level of quality and safety has been maintained.

Further, 10 CFR 50.55a(b)(2)(xv)(A)(2) states, "Where examination from both sides is not possible on austenitic welds or DM 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."

Based on the design configuration of the components and available examinations techniques, Calvert Cliffs was not able to achieve 100 percent coverage of the susceptible material examination volume and/or essentially 100 percent Code coverage of the required examination volume for the components listed without major modifications to the components. Although essentially 100 percent code coverage was not obtained, every effort was made to obtain the maximum amount of coverage as reasonably possible. The combination of coverage amount combined with the examination techniques discussed below, contributed to maintaining a high level of quality and safety.

7. Proposed Alternative and Basis for Use Dissimilar metal weld examinations performed at Calvert Cliffs during refueling outages conducted in 2010 (Unit 1) and 2011 (Unit 2) employed phased array (PA) ultrasonic testing (UT) technology.

Utilizing PA technology not only improves the overall effectiveness of the UT examination but also provides significant performance improvements when compared to conventional examination methodologies.

All DM welds were examined utilizing Structural Integrity's proprietary manual PA procedure, SI-UT-130 R3. This procedure has been qualified in accordance with the requirements of ASME Code,Section XI, Appendix VIII, Supplement 10 for the manual PA UT examination technique.

This technique has been Performance Demonstration Initiative-qualified to detect and characterize (length and depth size) service-induced damage associated with the weld in the form of PWSCC.

The SI-UT-130 R3 procedure is also qualified to scan DM welds with single-sided access. This single-sided access qualification allows for full interrogation of DM welds that have cast stainless steel safe ends, which restrict scanning from the cast stainless side. The application of Structural Integrity's PA UT technology allows for a reduction in the number of required examination scans across the surface of the component, while matching or exceeding the maximum achievable coverage of the Code-required weld and adjacent base material volume of any currently qualified ultrasonic technique. The capability of PA to provide increased examination coverage is inherently evident when applied to limited-access scanning surfaces.

Using the PA technique, examination coverage is greater than conventional techniques for constrained configurations. This is because the procedure employs a large number of discrete examination angles (including credit for a low angle of 30-degrees), which, in addition to increased examination coverage, provides superior material insonification by utilizing many different angular 5

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06) sound paths, thereby optimizing penetration into highly attenuative materials. The technique also includes a 10 degree electronic skew for circumferential scanning beam angles, which significantly improves examination coverage.

Structural Integrity's PA UT procedure provided an increased capability to more effectively interrogate the required ISI examination volume due to the use of a lower effective angle of 30 degree as compared to a typical 45 degree lead angle associated with most conventional UT procedures. Likewise, the surface limiting factors associated with other procedures, which apply linear scanning techniques, are not a factor when applying azimuthal PA UT techniques. The combined advantages of a qualified lower effective angle and a smaller surface contact requirement achieved by the application of azimuthal PA UT techniques, contributes to the reduced need for surface preparation and the ability to achieve maximum coverage of the examination volume.

Surface preparation efforts were conducted at Calvert Cliffs on various welds where it was deemed an improvement to examination coverage.

The major limitation to achieving essentially 100 percent coverage, and/or 100 percent coverage of the susceptible examination volume by reference of ASME Code Case N-770-1 in 10 CFR 50.55a, with conditions, is the presence of cast stainless steel. All DM welds >12 inches contain cast stainless steel safe ends. For these welds containing cast stainless steel items, no supplement is available in Section XI, Appendix VIII. Therefore, the required examination volume was examined by Section XI, Appendix VIII procedures to the maximum extent practical.

8. CONCLUSION In July 2011, the NRC incorporated by reference ASME Code Case N-770-1 into 10 CFR 50.55a.

Specific implementing requirements are documented in 10 CFR 50.55a(g)(6)(ii)(F). The relevant conditions applicable to Calvert Cliffs DM welds are shown in Table A.

Item (2) of 10 CFR 50.55a(g)(6)(ii)(F) requires the applicable DM welds to be categorized in accordance with ASME Code Case N-770-1, Table 1. This categorization has been performed and is included in this report. All components at hot leg operating temperatures have been previously mitigated by the MSIPTM process, and have met the performance criteria of Appendix I of ASME Code Case N-770-1 with the exception of obtaining essentially 100 percent coverage as identified in Table A.

All remaining DM welds have been categorized as Inspection Item B.

Item (3) of 10 CFR 50.55a(g)(6)(ii)(F) requires that baseline examinations for the welds in ASME Code Case N-770-1, Table 1 be completed by the end of the next refueling outage after January 20, 2012. Previous examinations may be credited if they have met the following criteria:

1. Examinations were performed using a procedure that meets the requirements of ASME Code Section XI, Appendix VIII and;

2. The Code required examination volume of essentially 100 percent coverage has been obtained.

If the previous examinations do not meet these requirements, they still can be used to meet the baseline examination requirements, provided that NRC approval of alternative inspection requirements is granted prior to the end of the next refueling outage after January 20, 2012.

6

ATTACHMENT (1)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 1 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-06)

Due to the fact that not including the examination volume scanned from the cast stainless steel side and specific geometric limitations prevents essentially 100 percent examination volume coverage from being obtained, relief is requested for an alternative in order for the examinations previously conducted at Calvert Cliffs to meet the baseline examination requirements of Item (3).

All examinations were performed in accordance with MRP-139 requirements and meet current ASME Code Case N-770-1 requirements. Results from the examinations were documented in the ISI refueling outage report. However with the conditions imposed by 10 CFR 50.55a(g)(6)(ii)(F) (3) and (4), all welds with cast stainless steel material do not meet these conditions. Therefore, reasonable assurance of quality and safety is based on the achieved coverage and the ASME Code Case N-722 VE examinations performed.

9. Duration of Proposed Alternative Relief is requested to accept the baseline examinations performed in 2010 for the Fourth Ten-year Interval of the ISI Program for Calvert Cliffs which was effective from October 2009, ending on June 30, 2019 for Unit 1.

7

ENCLOSURE 1 Unit 1 Examination Coverage Plots Calvert Cliffs Nuclear Power Plant, LLC December 29, 2011

CCNPP Unit 1 Examination Coverage 102300 / 30-RC-11A-7 ASME See XI Coverage limited due to cast stainless steel 60% ASME Section XI Coverage Obtained MRP-139 Coverage No Limitations 100% Coverage Limitation r - - -I I ASME Sec XI Volume I MRP-139 Volume I I ----------- -I ---------------- I 1

CCNPP Unit I Examination Coverage 102300 / 30-RC-11A-7 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage and due to configuration Limited due to configuration (85% MRP-139 Coverage Obtained)

(60% ASME Section XI Coverage Obtained)

Limitation Area r- -- -- -- -- -- - --- ------------ I I ASME Sec XI Volume I I MRP-139 Volume I I....................... I I ------------ I 2

CCNPP Unit 1 Examination Coverage 102450 / 30-RC-11A-10 ASME Sec XI Coverage limited due to Cast Stainless Steel and Cold Leg Spray Nozzle Obstruction (68% ASME Section XI Coverage Obtained)

MRP-139 Coverage limitation due to Cold Leg Spray Nozzle (98% MRP-139 Coverage) f I

Limitation Area r ------------ 1 ------------ I I ASME Sec XI Volume I I MRP-139 Volume I I------------I 3

CCNPP Unit 1 Examination Coverage 102450 / 30-RC-11A-10 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage and due to configuration Limited due to configuration (46% ASME Section XI Coverage Obtained) (79% MRP-139 Coverage Obtained) r - - -----------

I ASMIE Sec XI Volume I MRP-139 Volume I----------- - --- I ------------ I 4

CCNPP Unit 1 Examination Coverage 104550 / 30-RC-11B-7 ASME Sec XI Coverage limited due to cast stainless steel (65% ASME Section XI Coverage Obtained)

MRP-139 Coverage No Limitations 100% Coverage 14*07 r--- Z"*7 r-------------- I----------------I II -ASME

- - -Sec

- XI

- -Volume

- - - - - -I I MRP-139 Volume I I ------------ I 5

CCNPP Unit 1 Examination Coverage 104550 / 30-RC-11B-7 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage and due to configuration Limited due to configuration (49% ASME Section XI Coverage Obtained) (83% MRP-139 Coverage Obtained)

Limitation r- - -

Are I ASME Sec XI Volume I MRP-139 Volume I I I - ----------- I 6

CCNPP Unit 1 Examination Coverage 104700 / 30-RC-11B-10 ASME Sec XI Coverage limited due to Cast Stainless Steel and Cold Leg Spray Nozzle Obstruction (53% ASME Section XI Coverage Obtained)

MRP-139 Coverage limitation due to Cold Leg Spray Nozzle (98% MRP-139 Coverage)

I r- ------------- I ------------ I I ASME Sec XI Volume I MRP-139 Volume I

- -! I ------------ I 7

CCNPP Unit 1 Examination Coverage 104700 / 30-RC-11B-10 ASME Sec XI Coverage limited due to cast stainless steel and due to configuration (34% ASME Section XI Coverage Obtained)

II MRP-139 Coverage Limited due to configuration (79% MRP-139 Coverage Obtained) U Limitation Area

/

r---------- ---- ------------ I I ASME Sec XI Volume I I MRP-139 Volume I I ------------ I 8

CCNPP Unit 1 Examination Coverage 107450 / 30-RC-12A-7 ASME See XI Coverage limited due to cast stainless steel (70% ASME Section XI Coverage Obtained)

MRP-139 Coverage No Limitations 100% Coverage r- - ----------

I ASME Sec XI Volume I MRP-139 Volume I---------------------- I I ------------ I 9

CCNPP Unit 1 Examination Coverage 107450 / 30-RC-12A-7 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage and due to configuration Limited due to configuration (45% ASME Section XI Coverage Obtained) (81% MRP-139 Coverage Obtained)

Limitation 7 Are MI Sec XI Volume I MRP-139 Volume I I-----------------

I -------- I 10

CCNPP Unit 1 Examination Coverage 107600 / 30-RC-12A-10 ASME Sec XI Coverage limited due to cast stainless steel (63% ASME Section XI Coverage Obtained) 7"7 MRP-139 Coverage No Limitations 100% Coverage r-------------- I----------------I I ASME Sec XI Volume I IMRP-139 Volume I I ------------ I 11

CCNPP Unit 1 Examination Coverage 107600 / 30-RC-12A-10 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage and due to configuration Limited due to configuration (43% ASME Section XI Coverage Obtained) (81% MRP-139 Coverage Obtained)

Limitation Area r-------------- I ------------ I II -ASME

- - -Sec

- XI

- Volume

- - - - - - -I I MRP-139 Volume I I ------------ I 12

CCNPP Unit 1 Examination Coverage 109600 / 30-RC-12B-7 ASME Sec XI Coverage limited due to cast stainless steel (62% ASME Section XI Coverage Obtained)

MRP-139 Coverage No Limitations 100% Coverage r -*--

I ASME Sec XI Volume M

-- - - --------- ---------MRP-139

- Volume 13

CCNPP Unit 1 Examination Coverage 109600 / 30-RC-12B-7 ASME Sec XI Coverage limited due to cast stainless steel and due to configuration (45% ASME Section XI Coverage Obtained)

MRP-139 Coverage Limited due to configuration (83% MRP-139 Coverage Obtained) r- - -----------

I ASME Sec XI Volume I MRP-139 Volume I -I----------------- I ------ I 14

CCNPP Unit 1 Examination Coverage 109750 / 30-RC-12B-10 ASME Sec XI Coverage limited due to cast stainless steel (71% ASME Section XI Coverage Obtained)

MRP-139 Coverage No Limitations 100% Coverage Limitation Area I ASMESecXIVolume 1 IMRP-139 Volume I-------------I I 15

CCNPP Unit 1 Examination Coverage 109750 / 30-RC-12B-10 ASME Sec XI Coverage limited due to cast stainless steel MRP-139 Coverage (50% ASME Section XI Coverage Obtained) (83% MIRP-139 Coverage Obtained)

Limitation Area~

r ---------------

I ASME Sec XI Volume IM -139Volume I I--------------------

16

CCNPP Unit l

Examination Coverage 110450/ I 2-PSL-1 ASME Sec XI Axial Coverage 63%

MRP-1 3 9 Axial coverage 100%

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CCNPP Unit I Examination Coverage 111100 / 12-PSL-13 ASME Sec XI Axial Coverage 61%

MRP- 139 Axial Coverage 100%

Limitation Area r-------------- ------------ I 1 ASME Sec XI Volume I MRP-139 Volume I- - - - -- ---- - - --- I I ------------ I 19

I Unit CCNpp Coverage Examination

/ 12-PSL-l3 111100 57%

Coverage XICircumferential ASME Sec 94%

Coverage Circurnferential MRP-13 9 10 Limitation

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CCNPP Unit 1 Examination Coverage 113150 / 12-SC-1004-1 ASME Sec XI Axial Coverage 71%

MRP-139 Axial Coverage 100%

r-------------- I ------------ I I ASME Sec XI Volume I I MRP-139 Volume 21

CCNPP Unit 1 Examination Coverage 113150 / 12-SC-1004-1 ASME Sec XI Circumferential Coverage 70%

MRP-139 Circumferential Coverage 98%

r - - -----------

! ASME Sec XI Volume ! MRP-139 Volume I- I I------------

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114350 / 12.SI-10O9-16 ASME Sec XI Axia, Coverage 650/

MRP-1 3 9 Ayia Coverae 00 1

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Limitation Mea I SM~Sec YXVlui I I ,,

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CCNPP Unit 1 Examination Coverage 115200 / 12-SI-1010-14 ASME Sec XI Axial Coverage 62%

MRP- 139 Axial Coverage 100%

Limitation Arai r------------- ------------------

! ASME Sec XI Volume I I MRP-139 Volume I

- I------------I 25

CCNPP Unit 1 Examination Coverage 115200 / 12-SI-1010-14 ASME Section XI Circumferential Coverage 32%

MRP-139 Circumferential Coverage 73%

r- - -----------

! ASME Sec XI Volume I MRP-139 Volume I I- II------------

I 26

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ATTACHMENT (2)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 2 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-07)

Calvert Cliffs Nuclear Power Plant, LLC December 29, 2011

ATTACHMENT (2)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 2 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-07)

1. ASME Code Component(s) Affected Code Class 1 PWR Pressure Retaining Dissimilar Metal Piping and Vessel Nozzle Butt Welds Containing Alloy 82/182. American Society of Mechanical Engineers (ASME) Code Case N-770-1, Table 1, Examinations Categories, Inspection Item B - Unmitigated butt weld at cold leg operating temperature, Inspection Item D - Uncracked butt weld mitigated with stress improvement, Inspection Item E - Cracked butt weld mitigated with stress improvement.

2. Applicable Code Edition and Addenda ASME Boiler and Pressure Vessel Code,Section XI, 2004 Edition, no Addenda - Code Case N-770-1 subject to conditions specified in 10 CFR 50.55a(g)(6)(ii)(F)(2 through 10).

3. Applicable Code Requirement With the issuance of a revised 10 CFR 50.55a in July 2011, the Nuclear Regulatory Commission (NRC) incorporated by reference ASME Code Case N-770-1, "Alternative Examination Requirements and Acceptance Standards for Class I PWR Piping and Vessel Nozzle Butt Welds Fabricated with UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities,Section XI, Division 1" (ASME Approval Date: December 25, 2009).

Specific implementing requirements are documented in 10 CFR 50.55a(g)(6)(ii)(F) and are listed below.

(1) Licensees of existing, operating pressurized-water reactors as of July 21, 2011 shall implement the requirements of ASME Code Case N-770-1, subject to the conditions specified in paragraphs (g)(6)(ii)(F)(2) through (g)(6)(ii)(F)(10) of this section, by the first refueling outage after August 22, 2011.

(2) Full structural weld overlays authorized by the NRC staff may be categorized as Inspection Items C or F, as appropriate; welds that have been mitigated by the Mechanical Stress Improvement Process (MSIPTM) may be categorized as Inspection Items D or E, as appropriate, provided the criteria in Appendix I of the code case have been met; for Inservice Inspection (ISI) frequencies, all other butt welds that rely on Alloy 82/182 for structural integrity shall be categorized as Inspection Items A-I, A-2, or B until the NRC staff has reviewed the mitigation and authorized an alternative code case Inspection Item for the mitigated weld, or until an alternative code case Inspection Item is used based on conformance with an ASME mitigation code case endorsed in Regulatory Guide 1.147 with conditions, if applicable, and incorporated in this section.

(3) Baseline examinations for welds in ASME Code Case N-770-1, Table 1, Inspection Items A-I, A-2, and B, shall be completed by the end of the next refueling outage after January 20, 2012.

Previous examinations of these welds can be credited for baseline examinations if they were performed within the re-inspection period for the weld item in ASME Code Case N-770-1, Table 1 using Section XI, Appendix VIII requirements and met the Code required examination volume of essentially 100 percent. Other previous examinations that do not meet these requirements can be used to meet the baseline examination, requirement, provided NRC approval of alternative inspection requirements in accordance with paragraphs (a)(3)(i) or (a)(3)(ii) of this section is granted prior to the end of the next refueling outage after January 20, 2012.

I

ATTACHMENT (2)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 2 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-07)

(4) The axial examination coverage requirements of -2500(c) may not be considered to be satisfied unless essentially 100 percent coverage is achieved.

Items (5) through (9) of 10 CFR 50.55a(g)(6)(ii)(F) address future inspections beyond the baseline examination and are therefore not discussed in this relief request. Item (10) of 10 CFR 50.55a(g)(6)(ii)(F) addresses a mitigation that Calvert Cliffs does not have and is therefore not discussed in this relief request.

4. Reason for Request The relevant conditions for this relief request are items (2) through (4) of 10 CFR 50.55a(g)(6)(ii)(F). These requirements are applicable to the welds listed in Table A below. Item (2) addresses defining the appropriate Inspection Item. Item (3) addresses performing the required baseline examination for that Inspection Item, while item (4) addresses the required examination coverage.

Item (2) of 10 CFR 50.55a(g)(ii)(F) requires that welds that have been mitigated by the MSIPTM may be categorized as Inspection Items D or E, as appropriate, provided the criteria in Appendix I of the Code Case have been met.

Item (3) of 10 CFR 50.55a(g)(6)(ii)(F) requires that all Inspection Items A-i, A-2, and B receive a baseline examination by the end of the first refueling outage after January 20, 2012. This report evaluates each location based on the specific Inspection Item frequency and examination coverage.

Whereas MRP-139 and ASME Code Case N-770-1 made allowances for axial examination coverage of dissimilar metal (DM) welds, the NRC has stated in item (4) above that essentially 100 percent coverage is required. This applies to meeting the baseline requirements for Item (3) above.

5. Component/Weld Scope The welds shown in Table A below are the applicable welds 2 inch nominal pipe size and greater covered by the requirements contained in ASME Code Case N-770-1, Section -1000. These welds have been categorized in accordance with Table I from ASME Code Case N-770-1. The ASME Section XI examination volume coverage achieved during the 2010 outage is also included in Table A below.

Examination coverage plots are included in Enclosure I for those inspections for which essentially 100 percent coverage was unable to be obtained.

2

ATTACHMENT (2)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 2 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-07)

TABLE A, UNIT 2 DM WELD POPULATION ASME ASME ASME MRP-139 Inspection Inpcin Section Scin Axial Scan Circ Scan MP19 Axial Scan MRP-139 Circ Scan DM Weld Designator / Nozzle Item XI MRP-139 ID Location Size Category Coverage (%) (%) Coverage (%) (%) Notes 109280 / 30-RC-21A-7 21A RCP Inlet 30" B 57.60% 68.6 46.5 91.50% 100 83 1,5 109310 / 30-RC-21A-10 21A RCP Outlet 30" B 57.50% 64 51 89.50% 97 82 3,4,6 110280 / 30-RC-21B-7 21B RCP Inlet 30" B 35.00% 40.7 29.4 94.50% 100 89 1,4 110310 / 30-RC-21B-10 21B RCP Outlet 30" B 50.20% 60.3 40 89.50% 94 85 3,4,6 111280 / 30-RC-22A-7 22A RCP Inlet 30" B 49.00% 55 43 92.50% 100 85 1,4 111310 / 30-RC-22A-10 22A RCP Outlet 30" B 62.60% 68.2 57 92.50% 100 85 1,4,5,7 112280 / 30-RC-22B-7 22B RCP Inlet 30" B 51.00% 58 44 93.50% 100 87 1,4 112310 / 30-RC-22B-10 22B RCP Outlet 30" B 61.00% 72 50 87.00% 100 74 1,4 113010 / 12-PSL-1 PZR Surge @ PZR 12" D 57.00% 57 57 100% 100 100 1,2 PZR Surge @ RCS Hot 113130/ 12-PSL-13 Leg 12" D 70.50% 70.5 70.5 100% 100 100 1,2 Shutdown Cooling to RCS 114900 / 12-SC-2004-1 Hot Leg 12" D 61.00% 61 61 100% 100 100 1,2 Safety Injection to 21B 115140 / 12-SI-2009-15 Cold Leg 12" B 68.00% 68 68 100% 100 100 1,2 Safety Injection to 21A 116190 / 12-SI-2010-13 Cold Leg 12" B 71.00% 71 71 100% 100 100 1,2 Safety Injection to 22B 117120 / 12-SI-2011-13 Cold Leg 12" B 68.50% 68.5 68.5 100% 100 100 1,2 Safety Injection to 22A 118120 / 12-SI-2012-13 Cold Leg 12" B 71.00% 71 71 100% 100 100 1,2 136090 / 4-PS-2003-8 PZR Spray 4" D 84.00% 100 68 87% 100 74 1,4 PZR Spray from 21A 137010 / 3-PS-2001-1 Cold Leg 3" B 100% 100 100 100% 100 100 1,2 PZR Spray from 21B 138010 / 3-PS-2002-1 Cold Leg 3" B 100% 100 100 100% 100 100 1,2 141000 / 4-SR-2005-1 PZR Safety/Relief 4" D 100% 100 100 100% 100 100 1,2 3

ATTACHMENT (2)

RELIEF REQUEST FOR CALVERT CLIFFS UNIT 2 DISSIMILAR METAL BUTT WELD EXAMINATIONS (RR-ISI-04-07)

TABLE A, UNIT 2 DM WELD POPULATION ASME ASME MRP-139 Inspection Section Axial Circ Axial MRP-139 DM Weld Designator / Nozzle Item XI Scan Scan MRP-139 Scan Circ Scan ID Location Size Category- Coverage (%) (%) Coverage (%) (%) Notes 142000 / 4-SR-2006-1 PZR Safety/Relief 4" D 100% 100 100 100% 100 100 1, 2 156530 / 2-CV-2021-34 22B Charging Inlet 2" B 100% 100 100 100% 100 100 1,2,8 152440 / 2-CV-2005-30 21A Charging Inlet 2" B 100% 100 100 100% 100 100 1,12 157010 / 2-DR-2003-1 21A Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,2 158010 / 2-DR-2004-1 21B Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,2 160010 / 2-DR-2006-1 22B Cold Leg Drain 2" B 100% 100 100 100% 100 100 1,2 Locations in Bold operate at Cold Leg temperature.