ML091940536
| ML091940536 | |
| Person / Time | |
|---|---|
| Site: | North Anna  (NPF-004) |
| Issue date: | 07/13/2009 |
| From: | Funderburk C Dominion Resources Services, Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 09-344 | |
| Download: ML091940536 (7) | |
Text
Dominion Resources Services, Inc.
,11011 Dominion Boulevard, Clen Allen, VA.:\\1",
- ,\\,*h\\ddress: www.dorn.com July 13, 2009 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
NORTH ANNA POWER STATION UNIT 1 STEAM GENERATOR TUBE INSPECTION REPORT Serial No.
NL&OS/ETS Docket No.
License No.09-344 50-338 NPF-4 Pursuant to Technical Specification 5.6.7 for North Anna Power Station Unit 1, Dominion is required to submit a 180-day steam generator tube inspection report. The attachment to this letter provides the steam generator tube inspection report for the North Anna Unit 1 spring 2009 refueling outage.
This letter does not establish any new commitments.
Should you have any questions or require additional information, please contact Mr. Thomas Shaub at (804) 273-2763.
Very truly yours,
(;;;>y-C. L. Funderburk, Director Nuclear Licensing and Operations Support Dominion Resources Services, Inc.
for Virginia Electric and Power Company Attachment
cc:
U.S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW Suite 23T85 Atlanta, Georgia 30303 NRC Senior Resident Inspector North Anna Power Station Mr. J. E. Reasor, Jr.
Old Dominion Electric Cooperative Innsbrook Corporate Center 4201 Dominion Blvd.
Suite 300 Glen Allen, Virginia 23060 Ms. D. N. Wright NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North MaiI Stop 0-8 H4A 11555 Rockville Pike Rockville, Maryland 20852 Mr. J. F. Stang, Jr.
NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North MaiI Stop 0-8 G9A 11555 Rockville Pike Rockville, Maryland 20852 Serial No.09-344 Docket No. 50-338 180-Day SG Report Page 2 of 2
Serial No.09-344 Docket No. 50-338 180-Day SG Report ATTACHMENT NORTH ANNA UNIT 1 180-DAY NRC REPORT REGARDING STEAM GENERATOR TUBE INSPECTION PER TECHNICAL SPECIFICATION 5.6.7 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
Serial No.09-344 Docket No. 50-338 180-Day SG Report Page 1 of 4 SPRING 2009 - NORTH ANNA UNIT 1 STEAM GENERATOR INSPECTIONS The following satisfies the North Anna Power Station Technical Specification (T8) reporting requirement section 5.6.7.
During the North Anna spring 2009 refueling
- outage, steam generator (8G) inspections in accordance with TS 5.5.8.d were completed for two of the three steam generators ("B" and "C").
This was the second inspection under the modified Technical Specifications resulting from the TSTF-449 generic specification issued to the industry.
Initial entry into Mode 4 occurred on March 31, 2009 (11 :05 Hrs). Therefore, this report is required to be submitted by September 27, 2009.
Italicized wording represents TS verbiage.
The required information is provided under each reporting requirement as follows:
A report shall be submitted within 180 days after the initial entry into Mode 4 following completion of an inspection performed in accordance with the Specification 5.5.8, "Steam Generator (SG) Program." The report shall include:
- 8. The scope of inspections performed on each SG The following primary side inspections were performed in steam generators "B" and Video examination of all four channel heads (as-tound/as-lett),
specifically including all plugs.
100% full-lanqth tube inspection utilizing bobbin coil probe for all tubes except for Row 1 U-bends.
20% (720 tubes in SG Band 719 tubes in SG C) hot leg top-ot-tubsshset (+/- 3")
utiliZing a rotating coil probe with tube selection biased toward secondary side critical areas in the sludge zone, peripheral area tubes, and the remainder across the tubesheet.
100% Row 1 (98 tubes in each SG) of the U-bend region utilizing rotating coil probe.
Special interest inspections dents/dings (> 2 volts) with a rotating coil probe (Sample size: SG "B" 88% of hot leg indications, 33% all locations; SG "O" 76%
of hot leg indications, 35% all locations).
Special interest inspections of all bulge indications (> 2 volts) with a rotating coil probe. (SG "B" - 5 inspections; SG "C" - 2 inspections)
Rotating coil probe inspection of bobbin identified I-codes (i.e.
possible indications) (Sample size: SG "B" - 5 tests; SG "C" - 0 tests).
Special interest of largest voltage tubesheet overexpansions (OXP) with a
rotating coil probe (Sample: SG "B" 20 hot leg tests and 4 cold leg tests; SG "C" 38 hot leg tests and 4 cold leg tests).
Serial No.09-344 Docket No. 50-338 180-Day SG Report Page 2 of 4 The following secondary side inspections were performed in steam generators "8" and "G":
Steam drum upper components visual inspection, which included the primary and secondary moisture separators, drain piping, and related components.
Video inspection of the upper tube bundle U-bend area.
Video inspection of the uppermost tube support plate (TSP), which included the i h TSP in the periphery area and in-bundle at selected tube columns.
The 4th, 51h, and 6th TSPs were also video inspected in the center bundle area accessed from the i h TSP.
Video inspection of the inside interface of the feed ring to J-nozzle joints.
High pressure water lancing was performed in all steam generators with post-lancing top-of-tubesheet video inspections to check for cleanliness and the presence of foreign objects.
- b. Active degradation mechanisms found No indications of tube degradation were identified in steam generators "B" and "G".
The only indication of tube degradation identified was the superficial scratching/wear identified on the secondary side of the SG "A" when a foreign object (carbon steel metal shaving) was removed after sludge lancing.
The secondary side visual inspections performed on the upper internals of the "B" and "C"
steam generators indicated no component degradation that would compromise tube integrity.
- c. Nondestructive examination techniques utilized for each degradation mechanism Inspections focused on the following degradation mechanisms listed in Table 1 utilizing the referenced eddy current techniques.
Serial No.09-344 Docket No. 50-338 180-Day SG Report Page 3 of 4 Table 1 Insgection Method for Applicable Degradation Modes I.*.*.*.*.*.*.*.*.>>>.......>1/>
[)e~radation I>*'-:ion,) I*****************
- v..,.....ype Mechanism Iii**
ii>i Bobbin - Detection Potential Tube Wear Anti-Vibration Bars Bobbin and -Point"
- Sizing Flow Distribution Bobbin Detection Potential Tube Wear Baffle Bobbin and -Potnt' - Sizing Tube Support Bobbin - Detection Existing Tube Wear Plate Bobbin and -Polnt" - Sizing Straight Leg &
Bobbin - Detection Potential Tube Wear AVB Tangents Bobbin or +Point'- Sizing (Row 8, 14, 26)
Tube Wear Bobbin - Detection Existing (foreign Freespan and TTS
+Point'- Sizing objects)
Hot Leg Top-of-Bobbin and +Point'- Detection Potential ODSCC Tubesheet Sludge
+Point'- Sizing Pile Area Hot Leg Top-of-Tubesheet Relevant/Informational Sludge Pile Area
+Point'
- Detection and Sizing PWSCC and Inspection Within Tubesheet Anomaly locations Relevant/Informational ODSCC Row 1 U-bends
-Polnt" - Detection and Sizing Inspection PWSCC Relevant/Informational ODSCC Freespan and
-Point'" - Detection and Sizing Inspection Tube Supports Relevant/Informational Top-of-Tubesheet Bobbin and -Point' - Detection Inspection OD Pitting
+Point'- Sizing
Serial No.09-344 Docket No. 50-338 180-Day SG Report Page 4 of 4
- d. Location, orientation (if linear), and measured sizes (if available) of service induced indications No tube wall degradation was detected during the eddy current examinations of steam generators "B" and "C".
- e. Number of tubes plugged during the inspection outage for each active degradation mechanism No tubes were plugged during the subject inspection.
f.
Total number and percentage of tubes plugged to date A total of two (2) tubes have been plugged in the North Anna Unit 1 steam generators.
Specifically, "A" - 0 (0%), "B" - 0 (0%), "C" - 2 (0.06%) with an overall tube plugged percentage of 0.02 %.
- g. The results of condition monitoring, including the results of tube pulls and tn-situ testing The Condition Monitoring Evaluation was completed and steam generators "B" and "C" did not exceed any performance criteria during the last cycle since the fall 2007 inspections.
No findings during the spring 2009 inspection of steam generators "B" and "C" invalidated the previous operational assessment for any of the three steam generators. Condition monitoring requirements were met. Therefore, tube pulls and in-situ pressure testing were not necessary.
- h. The effective plugging percentage for all plugging in each SG There are no sleeves installed in the North Anna Unit 1 steam generators therefore, the effective plugging percentage remains the same as stated in (f) above.