ML070580143

Request for Additional Information Regarding the Relief Request No. CMP-020, Rev. 1

ML070580143
Person / Time
Site:	North Anna
Issue date:	02/27/2007
From:	Siva Lingam NRC/NRR/ADRO/DORL/LPLII-1
To:	Christian D Virginia Electric & Power Co (VEPCO)
Lingam, Siva NRR/DORL 415-1564
References
TAC MD4007
Download: ML070580143 (5)

Text

February 27, 2007 Mr. David A. Christian Senior Vice President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711

SUBJECT:

NORTH ANNA POWER STATION, UNIT NO. 2, REQUEST FOR ADDITIONAL INFORMATION (RAI) REGARDING THE RELIEF REQUEST NO. CMP-020, REVISION 1 (TAC NO. MD4007)

Dear Mr. Christian:

By letter dated January 9, 2007, Virginia Electric and Power Company (the licensee), submitted Relief Request CMP-020, Revision 1, associated with the partial examination of reactor pressure vessel (RPV) head-to-flange welds. The proposed relief request will allow a change in the inspection frequency and coverage of the RPV head-to-flange welds. The Nuclear Regulatory Commission (NRC) staff is reviewing the submittal and has determined that additional information is required to complete its evaluation.

The NRC staffs RAI is enclosed. The licensee is requested to provide a response to the RAI within 30 days.

Sincerely,

/RA/

Siva P. Lingam, Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-339

Enclosure:

RAI cc w/encl: See next page

ML070580143 NRR-088 OFFICE NRR/LPL2-1/PM NRR/LPD2-1/LA NRR/DCI/CVIB/BC NRR/LPL2-1/BC NAME SLingam MOBrien MMitchell EMarinos DATE 2/26/07 2/26/07 2/12/07* 2/27/07 REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST CMP-020, REVISION 1 REACTOR PRESSURE VESSEL HEAD-TO-FLANGE WELD NORTH ANNA POWER STATION, UNIT NO. 2 DOCKET NO. 50-339 Relief Request (RR) No. CMP-020, Revision 1, is for the third 10-year inservice inspection (ISI) interval, in which the licensee adopted the 1995 edition through the 1996 addenda of American Society of Mechanical Engineers (ASME) Code, Boiler and Pressure Vessel Code (Code),

Section XI as the ASME Code of record.

In accordance with Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 50.55a(a)(6)(i), the licensee submitted the North Anna Power Station, Unit 2, RR requesting approval to examine the accessible volumes of reactor pressure vessel (RPV) head-to-flange welds to the extent possible in lieu of the essentially 100% volume examination requirement specified in the ASME Code. In addition, the proposal included that the pre-service examinations already completed at the reduced coverage be counted as meeting the ASME Code requirements.

It appears that, based on the stated alternative in the RR,Section V of the attachment to licensees letter dated January 9, 2007, that the licensees intent is to use the pre-service examinations as an alternative for the scheduled second period, third 10-year ISI interval ASME Code,Section XI volumetric examinations. The purpose of the pre-service examinations is to establish a base line for the 10-year ISI interval ASME Code,Section XI examinations. Since the purpose of the periodical 10-year ISI interval ASME Code,Section XI examinations is to ensure that components are maintaining their structural integrity with respect to inservice degradation during a period of operation, the pre-service examinations can not be substituted for the periodical 10-year ISI interval ASME Code,Section XI examinations.

In the licensees cover letter dated January 9, 2007, the licensee stated that it is requesting a revision to the inspection frequency and coverage included in the RR (one third of the weld in each period) to reduce the impact of the RPV head inspection effort on the outage schedule.

Clarify the stated proposed alternative in Section V of the attachment to licensees letter dated January 9, 2007, as compared to the alternative stated in the last paragraph on page 1 of the licensees cover letter dated January 9, 2007.

Section V (As Stated)

The reactor pressure vessel head-to-flange weld will be examined in the third period to the extent permitted by the configuration of the reactor pressure vessel closure head as radiologically practical.

Enclosure

In addition, it is proposed that the pre-service examinations already completed at the reduced coverage be counted as meeting the [ASME] Code requirements.

Last Paragraph on Page 1 of Licensees Cover Letter Dated January 9, 2007 (As Stated)

During the upcoming spring 2007 Unit 2 refueling outage (the last refueling outage of the second period of the third interval), the North Anna Unit 2 RPVH [RPV head] is scheduled for a bare metal visual examination of 100 percent of the RPV head surface (including 360° around each RPV head penetration nozzle) in accordance with the revised NRC order EA-003-009, dated February 20, 2004. A volumetric examination of the RPVH penetrations is also scheduled to be performed from under the head. Due to the amount of inspection activity scheduled for the head. Dominion is requesting a revision to the inspection frequency and coverage included in CMP-020 (one third of the weld in each period) to reduce the impact of the RPVH inspection effort on the outage schedule. The proposed frequency and coverage schedule is consistent with ASME Code Section IWB-2412(a) which allows one weld to be examined in any period during the interval. It is proposed that the inspection of the RPVH head-to-flange weld be completed in the third period of the third interval. The attached relief has been revised to include the modified inspection frequency and coverage.

North Anna Power Station, Units 1 & 2 cc:

Mr. David A. Christian Senior Resident Inspector Senior Vice President North Anna Power Station and Chief Nuclear Officer U. S. Nuclear Regulatory Commission Virginia Electric and Power Company P. O. Box 490 Innsbrook Technical Center Mineral, Virginia 23117 5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. Daniel G. Stoddard Site Vice President Mr. C. Lee Lintecum North Anna Power Station County Administrator Virginia Electric and Power Company Louisa County Post Office Box 402 Post Office Box 160 Mineral, Virginia 23117-0402 Louisa, Virginia 23093 Dr. Robert B. Stroube, MD, MPH Ms. Lillian M. Cuoco, Esq. State Health Commissioner Senior Counsel Office of the Commissioner Dominion Resources Services, Inc. Virginia Department of Health Building 475, 5 th floor Post Office Box 2448 Rope Ferry Road Richmond, Virginia 23218 Waterford, Connecticut 06385 Dr. W. T. Lough Virginia State Corporation Commission Division of Energy Regulation Post Office Box 1197 Richmond, Virginia 23218 Old Dominion Electric Cooperative 4201 Dominion Blvd.

Glen Allen, Virginia 23060 Mr. Chris L. Funderburk, Director Nuclear Licensing & Operations Support Dominion Resources Services, Inc.

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