ML081830468
| ML081830468 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/08/2008 |
| From: | John Lamb NRC/NRR/ADRO/DORL/LPLI-2 |
| To: | Christian D Virginia Electric & Power Co (VEPCO) |
| Lamb John G./NRR/DORL, 415-3100 | |
| References | |
| TAC MD8659 | |
| Download: ML081830468 (5) | |
Text
July 8, 2008 Mr. David A. Christian President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
MILLSTONE POWER STATION - UNIT 3 - REQUEST FOR ADDITIONAL INFORMATION REGARDING THE 2007 STEAM GENERATOR TUBE INSPECTIONS (TAC NO. MD8659)
Dear Mr. Christian:
By letters dated May 8, 2007 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML071350249), and April 11, 2008 (ADAMS Accession No. ML081140138), Dominion Nuclear Connecticut, Inc. (DNC) submitted information summarizing the results of the 2007 steam generator tube inspections at Millstone Power Station, Unit 3 (MPS3). These inspections were performed during the eleventh refueling outage (3R11).
The U.S. Nuclear Regulatory Commission staff has reviewed the information DNC provided and determined that additional information is required in order to complete the evaluation as set forth in the Enclosure.
The draft questions were sent to Mr. Bill Bartron, of your staff, to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. During a discussion with your staff on July 1, 2008, it was agreed that you would provide a response by September 19, 2008.
Sincerely,
/ra/
John G. Lamb, Senior Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No.: 50-423
Enclosure:
Request for Additional Information
ML081140138), Dominion Nuclear Connecticut, Inc. (DNC) submitted information summarizing the results of the 2007 steam generator tube inspections at Millstone Power Station, Unit 3 (MPS3). These inspections were performed during the eleventh refueling outage (3R11).
The U.S. Nuclear Regulatory Commission staff has reviewed the information DNC provided and determined that additional information is required in order to complete the evaluation as set forth in the Enclosure.
The draft questions were sent to Mr. Bill Bartron, of your staff, to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. During a discussion with your staff on July 1, 2008, it was agreed that you would provide a response by September 19, 2008.
Sincerely,
/ra/
John G. Lamb, Senior Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No.: 50-423
Enclosure:
Request for Additional Information DISTRIBUTION:
PUBLIC LPL1-2 R/F RidsNrrDorlLpl1-2 Resource RidsNrrPMCSanders Resource RidsNrrLAABaxter Resource RidsRgn1MailCenter Resource RidsAcrsAcnw_MailCTR Resource RidsOgcRp Resource RidsNrrPMJHughey Resource RidsNrrPMJLamb Resource RidsNrrDciCsgb Resource
- via memo (ML081690414)
ADAMS Accession No.: ML081830468
ENCLOSURE REQUEST FOR ADDITIONAL INFORMATION 2007 STEAM GENERATOR TUBE INSPECTIONS MILLSTONE POWER STATION UNIT 3 DOCKET NUMBER 50-423 By letters dated May 8, 2007 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML071350249), and April 11, 2008 (ADAMS Accession No. ML081140138), Dominion Nuclear Connecticut, Inc. (DNC or the licensee) submitted information summarizing the results of the 2007 steam generator (SG) tube inspections at Millstone Power Station, Unit 3 (MPS3). These inspections were performed during the eleventh refueling outage (RFO), called 3R11. In order for the U.S. Nuclear Regulatory Commission staff to complete its review of the documents listed above, the staff needs the following additional information:
- 1. For each RFO and SG tube inspection (including mid-cycle inspections), please provide the effective full power months of operation that the SGs had accumulated.
- 2. Please provide the scope of the secondary side inspections performed in SG A and C during the 2007 RFO, as referenced on page 3 of the April 11, 2008, letter. Also, please discuss the scope and results of any secondary side inspections that were not related to foreign object search and retrieval.
- 3. Regarding your rotating probe examinations, please clarify the following:
- a. The axial extent of the Hot Leg Transition examinations (e.g., 3-inches above to 3-inches below the top of the tubesheet);
- b. The percentage of overexpansions and bulges examined in SGs B and D; and
- c. The scope of inspections of dents and dings.
- 4. Regarding your inspections for possible loose parts and wear attributed to loose parts, please address the following:
- a. For the cold-leg, it appears that the bobbin coil was mainly relied on for detecting possible loose parts and wear attributed to loose parts. Please discuss the extent to which a turbo mix was used to analyze the bobbin coil data to assist in detecting these indications.
- b. For the possible loose parts and wear attributed to loose parts that were detected, please discuss the extent to which the indications were detected through a review of the bobbin coil data, rotating probe data, or both. In addition, please discuss the extent to which any of these indications were initially found during visual inspection.
- c. It was indicated that no known foreign objects were left in SGs B and D. Please discuss the extent to which indications of possible loose parts were inspected visually.
Please discuss whether any wear indications attributed to loose parts were left in service. If these indications were left in service, please discuss the extent to which a visual inspection was performed to confirm the absence of the loose part.
- 5. Please clarify the difference between single volumetric indications and volumetric indications. What is the nature of these indications (e.g., wear from loose parts, intergranular attack)? Please discuss the extent to which these indications have changed with time.
- 6. Please discuss the extent to which tubes (both stress relieved and non-stress relieved tubes) with non-optimal tube processing (as evidenced by an offset in the eddy current data) have been identified (refer to Information Notice 2002-21, Supplement 1). Please discuss the extent to which these tubes were included in the special interest rotating probe examinations.
Millstone Power Station, Unit No. 3 cc:
Lillilan M. Cuoco, Esquire Senior Counsel Dominion Resources Services, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Edward L. Wilds, Jr., Ph.D.
Director, Division of Radiation Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 First Selectmen Town of Waterford 15 Rope Ferry Road Waterford, CT 06385 Mr. J. W. "Bill" Sheehan Co-Chair NEAC 19 Laurel Crest Drive Waterford, CT 06385 Mr. Evan W. Woollacott Co-Chair Nuclear Energy Advisory Council 128 Terry's Plain Road Simsbury, CT 06070 Senior Resident Inspector Millstone Power Station c/o U.S. Nuclear Regulatory Commission P. O. Box 513 Niantic, CT 06357 Ms. Nancy Burton 147 Cross Highway Redding Ridge, CT 00870 Mr. Joseph Roy, Director of Operations Massachusetts Municipal Wholesale Electric Company Moody Street P.O. Box 426 Ludlow, MA 01056 Mr. J. Alan Price Site Vice President Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Mr. Chris Funderburk Director, Nuclear Licensing and Operations Support Dominion Resources Services, Inc.
5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. William D. Bartron Licensing Supervisor Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Mr. David A. Sommers Dominion Resources Services, Inc.
5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. David A. Christian President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711