ML022790009

RAI, Annual Steam Generator Inservice Inspection Summary Report

ML022790009
Person / Time
Site:	North Anna
Issue date:	10/04/2002
From:	Stephen Monarque NRC/NRR/DLPM/LPD2
To:	Christian D Virginia Electric & Power Co (VEPCO)
References
TAC MB4593, TAC MB4594
Download: ML022790009 (4)

Text

October 4, 2002 Mr. David A. Christian Senior Vice President - Nuclear Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Blvd.

Glen Allen, Virginia 23060

SUBJECT:

NORTH ANNA POWER STATION, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING ANNUAL STEAM GENERATOR INSERVICE INSPECTION

SUMMARY

REPORT (TAC NOS. MB4593 AND MB4594)

Dear Mr. Christian The staff has reviewed your submittal dated February 28, 2002, that provided the annual steam generator inservice inspection report for North Anna Power Station, Units 1 and 2. Your response to the enclosed request for additional information (RAI) is required in order for the staff to complete this review.

Our questions are provided in the Enclosure. The staff requests a response to the RAI within 60 days of the date of this letter. This response was discussed with Mr. Tom Shaub of your licensing staff on September 30, 2002, who indicated that Virginia Electric and Power Company will be able to meet this date.

Sincerely,

/RA/

Stephen R. Monarque, Project Manager, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339

Enclosure:

As stated cc w/encl: See next page

October 4, 2002 Mr. David A. Christian Senior Vice President - Nuclear Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Blvd.

Glen Allen, Virginia 23060

SUBJECT:

NORTH ANNA POWER STATION, UNITS 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING ANNUAL STEAM GENERATOR INSERVICE INSPECTION

SUMMARY

REPORT (TAC NOS. MB4593 AND MB4594)

Dear Mr. Christian The staff has reviewed your submittal dated February 28, 2002, that provided the annual steam generator inservice inspection report for North Anna Power Station, Units 1 and 2. Your response to the enclosed request for additional information (RAI) is required in order for the staff to complete this review.

Our questions are provided in the Enclosure. The staff requests a response to the RAI within 60 days of the date of this letter. This response was discussed with Mr. Tom Shaub of your licensing staff on September 30, 2002, who indicated that Virginia Electric and Power Company will be able to meet this date.

Sincerely,

/RA/

Stephen R. Monarque, Project Manager, Section 1 Project Directorate II Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos. 50-338 and 50-339

Enclosure:

As stated cc w/encl: See next page Distribution: RidsAcrsAcnwMailCenter RidsRgn2MailCenter (KLandis)

PUBLIC SMonarque (paper copy) OGC PDII-1 Rdg. EDunnington (paper copy) RidsNrrDlpmLpdii KKarwoski Accession No. ML022790009 OFFICE PDII-1/PM PDII-2/LA PDII-1/SC NAME SMonarque EDunnington LOlshan for:

JNakoski DATE 10/04/02 10/04/02 10/04/02 OFFICIAL RECORD COPY

REQUEST FOR ADDITIONAL INFORMATION NORTH ANNA POWER STATION, UNITS 1 AND 2 STEAM GENERATOR INSERVICE INSPECTION

SUMMARY

REPORT

1. Please describe the basic design of the North Anna Power Station, Units 1 and 2 steam generators including information such as tube diameter (e.g., 7/8-inch), tube wall thickness (e.g., 0.050-inch), number of tubes (e.g., 3592), tube expansion method (e.g.,

hydraulic), tube support design (support plates and antivibration bars), tube pitch, etc.

Please include a sketch of the tube support plate naming convention and a tubesheet map in this description.

2. It was indicated that two techniques were used in sizing the indication found in steam generator C of North Anna, Unit 2 in Row 43, Column 56. Discuss whether the qualification data had indications that were observed at this location. Discuss whether any other diagnostic exams besides eddy current testing were performed on this tube (e.g., ultrasonic testing, visual, in-situ pressure testing).

The indication in this tube was located within the confines of the tube support plate (presumably during shutdown) and was believed to be mechanically induced. Discuss whether the indication would be expected to be within the tube support plate during normal operation. If not, discuss the effects on your operational assessment/root cause investigation.

One possible cause for this indication was that it was a result of a burr or some other small discrete particle located at the edge of one of the quatrefoil lands. Discuss whether any scratches or manufacturing burnishing marks are located on the portions of this tube below the 5th cold-leg tube support.

In assessing the growth rate of this indication, it was assumed that the indication initiated immediately upon placing the replacement steam generators in service. In the licensees 2000 Annual Report, it was indicated that antivibration bar wear indications in earlier F-type steam generators typically begin during the 4th to 5th cycle of operation.

Given the potential for wear-type indications not to initiate immediately upon start-up, discuss the basis for the assumption that this indication initiated at start-up.

3. Please clarify what is meant by "close gap antivibration wear tolerance techniques."

Refer to page 5 of 7 of Attachment 1 to the February 28, 2002, submittal.

Mr. David A. Christian North Anna Power Station Virginia Electric and Power Company Units 1 and 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 Ms. Lillian M. Cuocco, Esq. Mr. Richard H. Blount, II Senior Nuclear Counsel Site Vice President Dominion Nuclear Connecticut, Inc. Surry Power Station Millstone Power Station Virginia Electric and Power Company Building 475, 5 th floor 5570 Hog Island Road Rope Ferry Road Surry, Virginia 23883-0315 Rt. 156 Waterford, Connecticut 06385 Mr. Robert B. Strobe, M.D., M.P.H.

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