ML071350188
| ML071350188 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/17/2007 |
| From: | John Hughey NRC/NRR/ADRO/DORL/LPLI-2 |
| To: | Christian D Dominion Nuclear Connecticut |
| Hughey J, NRR/DORL, 301-415-3204 | |
| References | |
| TAC MD2102 | |
| Download: ML071350188 (5) | |
Text
1 ADAMS Accession Number ML051300243 2 ADAMS Accession Number ML060410115 3 ADAMS Accession Number ML070590190 May 17, 2007 Mr. David A. Christian Sr. Vice President and Chief Nuclear Officer Dominion Nuclear Connecticut, Inc.
Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
REVIEW OF STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT FOR THE 2005 REFUELING OUTAGE AT MILLSTONE POWER STATION, UNIT NO. 2 (TAC NO. MD2102)
Dear Mr. Christian:
By letter dated May 2, 20051, as supplemented by letters dated January 31, 20062 and February 19, 20073, Dominion Nuclear Connecticut, Inc. (DNC), submitted reports summarizing the steam generator tube inservice inspections performed at Millstone Power Station, Unit No. 2 (MPS2) during Refueling Outage 16 in April 2005. Copies of these letters have been placed in the Nuclear Regulatory Commission's (NRC's) Public Document Room and added to the Agencywide Documents Access and Management System (ADAMS) Public Electronic Reading Room. To view these documents visit http://www.nrc.gov/reading-rm/adams.html.
As discussed in the enclosed review, the NRC staff concluded that DNC provided the information required by the technical specifications for MPS2, and the NRC staff did not identify any technical issues that warranted follow-up action at this time. If you have any questions, please contact me at (301) 415-3204.
Sincerely,
/ra/
John D. Hughey, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-336
Enclosure:
As stated cc w/encl: See next page
1 ADAMS Accession Number ML051300243 2 ADAMS Accession Number ML060410115 3 ADAMS Accession Number ML070590190 May 17, 2007 Mr. David A. Christian Sr. Vice President and Chief Nuclear Officer Dominion Nuclear Connecticut, Inc.
Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
REVIEW OF STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT FOR THE 2005 REFUELING OUTAGE AT MILLSTONE POWER STATION, UNIT NO. 2 (TAC NO. MD2102)
Dear Mr. Christian:
By letter dated May 2, 20051, as supplemented by letters dated January 31, 20062 and February 19, 20073, Dominion Nuclear Connecticut, Inc. (DNC), submitted reports summarizing the steam generator tube inservice inspections performed at Millstone Power Station, Unit No. 2 (MPS2) during Refueling Outage 16 in April 2005. Copies of these letters have been placed in the Nuclear Regulatory Commission's (NRC's) Public Document Room and added to the Agencywide Documents Access and Management System (ADAMS) Public Electronic Reading Room. To view these documents visit http://www.nrc.gov/reading-rm/adams.html.
As discussed in the enclosed review, the NRC staff concluded that DNC provided the information required by the technical specifications for MPS2, and the NRC staff did not identify any technical issues that warranted follow-up action at this time. If you have any questions, please contact me at (301) 415-3204.
Sincerely,
/ra/
John D. Hughey, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-336
Enclosure:
As stated cc w/encl: See next page DISTRIBUTION:
PUBLIC Lpl1-2 R/F RidsNrrDorlLpl1-2 RidsNrrLACSola RidsNrrPMJHughey RidsOgcMailCenter RidsAcrsAcnwMailCenter RidsRgn1MailCenter KKarwoski Adams Accession No. ML071350188
- By Memo Dated OFFICE LPL1-2/GE LPL1-2/PM LPL1-2/PM LPL1-2/LA CSGB/BC LPL1-2/BC NAME CSanders JHughey GEMiller CSola AHiser*
HChernoff DATE 5/16/07 5/16/07 5/16/07 5/16/07 3/12/2007 5/17/07 OFFICIAL RECORD COPY
Enclosure UNITED STATES NUCLEAR REGULATORY COMMISSION REVIEW OF 2005 REFUELING OUTAGE STEAM GENERATOR TUBE INSERVICE INSPECTION RESULTS MILLSTONE POWER STATION, UNIT NO. 2 DOCKET NO. 50-336 By letter dated May 2, 2005, as supplemented by letters dated January 31, 2006, and February 19, 2007, Dominion Nuclear Connecticut, Inc (licensee), submitted information to the Nuclear Regulatory Commission (NRC) pertaining to steam generator (SG) tube inspections performed in 2005 at Millstone Power Station, Unit No. 2 (MPS2). These inspections were performed following Refueling Outage 16.
The two SGs at MPS2 were replaced in 1993 with SGs fabricated by Babcock and Wilcox International. Each SG nominally contains 8523 thermally treated Alloy 690 tubes. Each tube has a nominal outside diameter of 0.750 inch and a nominal wall thickness of 0.0445 inch. The tubes were hydraulically expanded at both ends for the full length of the tubesheet and are supported by a number of stainless steel tube support plates. The U-bends of the tubes installed in rows 1 through 8 were thermally stress relieved after bending.
The licensee provided the scope, extent, methods, and results of their SG tube inspections in the documents referenced above. In addition, the licensee described corrective actions (e.g., tube plugging) taken in response to the inspection findings. During the 2005 outage, steam generator tube inspections were only performed on SG 1; however, a secondary side inspection was performed in both SGs. The SGs had accrued 7.037 effective full power years of operation at the time of the 2005 outage.
Based on the review of the information provided, the NRC staff has the following observations:
A number of loose parts were identified during the inspections. No tube wear was associated with any of the loose parts and several of these parts were left in the SG (i.e., they were not removed). The licensee performed a review for the parts left in the steam generator to ensure that these parts would not result in unacceptable tube degradation.
No tubes have been reported that are in close proximity to each other.
All of the bulges in the steam generator have been present since the baseline examination. Although not all dent and ding signals reported are traceable to the baseline examination, the licensee concluded that these indications are most likely not service induced and are most likely the result of improvements in examination technology or reporting criteria.
Based on a review of the information provided, the NRC staff concludes that the licensee provided the information required by their technical specifications. In addition, the staff concludes that there are no technical issues that warrant follow-up action at this time, since the inspections appear to be consistent with the objective of detecting potential tube degradation, and the inspection results appear to be consistent with industry operating experience at similarly designed and operated units.
Millstone Power Station, Unit No. 2 cc:
Lillian 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 Charles Brinkman, Director Washington Operations Nuclear Services Westinghouse Electric Company 12300 Twinbrook Pkwy, Suite 330 Rockville, MD 20852 Senior Resident Inspector Millstone Power Station c/o U.S. Nuclear Regulatory Commission P.O. Box 513 Niantic, CT 06357 Mr. J. Alan Price Site Vice President Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor 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 Ms. Nancy Burton 147 Cross Highway Redding Ridge, CT 00870 Mr. Chris L. Funderburk Director, Nuclear Licensing and Operations Support Dominion Resources Services, Inc.
Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. David W. Dodson Licensing Supervisor Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Mr. Joseph Roy, Director of Operations Massachusetts Municipal Wholesale Electric Company Moody Street P.O. Box 426 Ludlow, MA 01056