ML020450647

ASME Section XI Inservice Inspection (ISI) Program Relief Request NDE-Partial-2, TAC No. MB1129

ML020450647
Person / Time
Site:	North Anna
Issue date:	02/13/2002
From:	Richard Laufer NRC/NRR/DLPM/LPD2
To:	Christian D Virginia Electric & Power Co (VEPCO)
Monarque S, NRR/DLPM, 415-1544
References
TAC MB1129
Download: ML020450647 (7)

Text

February 13, 2002 Mr. David A. Christian Senior Vice President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Blvd.

Glen Allen, Virginia 23060-6711

SUBJECT:

NORTH ANNA POWER STATION, UNIT 1 - ASME SECTION XI INSERVICE INSPECTION (ISI) PROGRAM RELIEF REQUEST NDE-PARTIAL-2 (TAC NO.

MB1129)

Dear Mr. Christian:

By letter dated January 29, 2001, as supplemented by letter dated November 26, 2001, you requested relief from certain requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, associated with examinations where only partial coverage could be obtained due to interferences and weld geometry.

Our evaluation and conclusion are contained in the enclosed Safety Evaluation. The staff has concluded that the requirements of Section XI of the ASME Code are impractical to perform, and the examinations that have been performed provide reasonable assurance of structural integrity of the subject welds. The relief you requested is authorized pursuant to Title 10 of the Code of Federal Regulations Section 50.55a(g)(6)(i) for the North Anna Power Station, Unit 1 third 10-year ISI interval.

Sincerely,

/RA/

Richard J. Laufer, Acting Chief, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-338

Enclosure:

As stated cc w/encl: See next page

ML020450647 *No major changes made to the SE OFFICE PM:PDII/S1 LA:PDII/S2 DE:EMCB* OGC ** SC/PDII/S1 NAME SMonarque EDunnington TChan AFernandez RLaufer DATE 02/12/02 02/12/02 01/16/02 02 /06/02 2/12/02 Mr. David A. Christian North Anna Power Station Virginia Electric and Power Company Unit 2 cc:

Mr. C. Lee Lintecum Mr. David A. Heacock County Administrator Site Vice President Louisa County North Anna Power Station P.O. Box 160 P.O. Box 402 Louisa, Virginia 23093 Mineral, Virginia 23117-0402 Mr. Donald P. Irwin, Esquire Mr. Richard H. Blount, II Hunton and Williams Site Vice President Riverfront Plaza, East Tower Surry Power Station 951 E. Byrd Street Virginia Electric and Power Company Richmond, Virginia 23219 5570 Hog Island Road Surry, Virginia 23883-0315 Dr. W. T. Lough Robert B. Strobe, M.D., M.P.H.

Virginia State Corporation State Health Commissioner Commission Office of the Commissioner Division of Energy Regulation Virginia Department of Health P.O. Box 1197 P. O. Box 2448 Richmond, Virginia 23209 Richmond, Virginia 23218 Old Dominion Electric Cooperative Mr. William R. Matthews 4201 Dominion Blvd. Vice President - Nuclear Operations Glen Allen, Virginia 23060 Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Mr. Stephen P. Sarver, Director Glen Allen, Virginia 23060-6711 Nuclear Licensing & Operations Support Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Blvd.

Glen Allen, Virginia 23060-6711 Office of the Attorney General Commonwealth of Virginia 900 East Main Street Richmond, Virginia 23219 Senior Resident Inspector North Anna Power Station U.S. Nuclear Regulatory Commission 1024 Haley Drive Mineral, Virginia 23117

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO THE THIRD 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION, UNIT 1 DOCKET NUMBER 50-338

1.0 INTRODUCTION

The Inservice inspection (ISI) of the American Society of Mechanical Engineers (ASME) Code Class 1, 2, and 3 components is to be performed in accordance with Section XI of the ASME Boiler and Pressure Vessel (B&PV) Code and applicable addenda as required by Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a(g), except where specific relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i).

Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components (including supports) shall meet the requirements, except the design and access provisions and the pre-service examination requirements, set forth in the ASME Code,Section XI, "Rules for Inservice Inspection (ISI) of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components and system pressure tests conducted during the first 10-year interval and subsequent intervals comply with the requirements in the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b) 12 months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The Code of record for the North Anna Power Station, Unit 1 third 10-year ISI interval is the 1989 Edition of the ASME Boiler and Pressure Vessel Code.

Pursuant to 10 CFR 50.55a(g)(5), if the licensee determines that conformance with an examination requirement of Section XI of the ASME Code is not practical for its facility, information shall be submitted to the Commission in support of that determination and a request made for relief from the ASME Code requirement. After evaluation of the determination, pursuant to 10 CFR 50.55a(g)(6)(i), the Commission may grant relief and may impose alternative requirements that are determined to be authorized by law, will not endanger life, property, or the common defense and security and are otherwise in the public interest, giving due consideration to the burden upon the licensee that could result if the requirements were imposed.

By letter dated January 29, 2001, as supplemented by a letter dated November 26, 2001, the Virginia Electric and Power Company (the licensee) submitted Request for Relief No.

NDE-Partial-2 for the third 10-year ISI program at the North Anna Power Station, Unit 1.

2.0 EVALUATION The information provided by the licensee in support of the request for relief from the ASME Code,Section XI (the Code) requirements has been evaluated and the basis for disposition is documented below.

2.1 Request for Relief No. NDE-Partial-2 2.2 Code Requirements:

The 1989 Edition of ASME Code,Section XI, Table IWC-2500-1, Examination Category C-A, Item Number C1.20, Examination Category C-C, Item Numbers C3.20 and C3.30, and Examination Category C-F-1, Item Numbers C5.11 and C5.21 do not allow any limitations to the required volumetric and surface examinations. Code Case N-460, Alternative Examination Coverage for Class 1 and Class 2 Welds, allows a reduction in coverage if it is less than 10%.

System/Components(s) for Which Relief is Requested:

Mark Weld No. Line No. Drawing No. Class 1 1-SI-TK-2 11715-WMKS-SI-TK-2 2 72H 14"-RH-2-602-Q2 11715-WMKS-0113A-1 2 WS-03 1-CH-P-1A 11715-WMKS-CH-P-1A 2 WS-04 1-CH-P-1A 11715-WMKS-CH-P-1A 2 11 3"-CH-81-1502-Q2 11715-WMKS-0111XA 2 64 14"-RH-3-602-Q2 11715-WMKS-0113A-2 2 2.3 Licensees Code Relief Request:

Relief is requested from examining the third-interval Code required volumetric and surface examinations for the identified head-to-shell, circumferential and tee valve welds, and welded supports. Relief is also requested for the pre-service examination of Weld 11.

In its submittal dated November 26, 2001, the licensee noted that Weld 11 at check valve 1-CH-279 on line 3"-CH-81-1502 received a pre-service radiography examination per construction code requirements ANSI B31.7, 1969 Edition, 1970 Addenda. The licensee is requesting relief from the ASME Code,Section XI pre-service volumetric examination coverage of less than 100%.

2.4 Licensees Basis for Requesting Relief Welds 1, 72H, WS-03, WS-04, 11, and 64 have been examined to the extent practical as required by the Code. Due to weld joint geometry and obstructions the reduction in coverage for the listed components was greater than 10%. Tables NDE-Partial-2-1, 2, 3, and 4 are provided detailing the limitations experienced. Amplifying sketches are also provided.

2.5 Licensees Proposed Alternative Examination It is proposed that the examinations already completed at the reduced coverage be counted as meeting the Code requirements.

Table NDE-Partial-2-1 North Anna, Unit 1 Examination Coverage Estimates Mark/Weld Category Item No. Scan Surface Reason for Partial Sketch No. Coverage % Coverage %

1 C-A C1.20 78 Support Legs 3 and 4 1 72H C-C C3.20 50 Support and Ceiling 2 and 3 Interference WS-03 C-C C3.30 78 Unable to Access Bottom of 4 Welded Support and Basemetal Due to Flange Connection WS-04 C-C C3.30 78 Unable to Access Bottom of 4 Support at Flange Radius Area 11 C-F-1 C5.21 87 Welded Joint configuration and 5 the short distance between the weld and the branch of the Tee 64 C-F-1 C5.11 72 Valve to elbow configuration 6 2.6 Staff Evaluation:

The Code requires 100% ultrasonic and/or surface examination of the subject welds. The staff has determined, from Sketches NDE-Partial-2-1 through NDE-Partial-2-6, that interferences from configuration, geometry, and other components preclude the complete ultrasonic and/or surface examination of the subject welds. Therefore, the Code requirements are impractical and to meet the Code requirements, design modifications would be necessary to provide access for examination. Imposition of the Code requirements would result in an undue burden on the licensee.

As shown on Tables NDE-Partial-2-1 through NDE-Partial-2-4, the licensee has examined a significant portion of the subject welds, obtaining 78% through 87% coverage for the completed Code volumetric examinations. For the Code surface examinations, the licensee obtained 50%

through 78% coverage. Based on the licensees volumetric and/or surface examinations that have been performed, any significant patterns of degradation should be detected by these examinations. Therefore, reasonable assurance of structural integrity of the subject components has been provided.

3.0 CONCLUSION

The staff concludes that the Code requirements are impractical to perform and the examinations that have been performed provide reasonable assurance of structural integrity of the subject welds. Therefore, relief is granted pursuant to 10 CFR 50.55a(g)(6)(i) for the third 10-year ISI interval. The staff has determined that granting relief is authorized by law and will not endanger life or property, or the common defense and security and is otherwise in the public interest giving due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.

Attachments: Sketches NDE-Partial-2-1 through NDE-Partial-2-6 Tables NDE-Partial-2-2 through NDE-Partial-2-4 Principal Contributor: T. McLellan Date: February 13, 2002