ML14028A256

Response to Request for Clarifying Information Regarding Steam Generator Tube Inservice Inspection Report for the Fall 2012 Refueling Outage

ML14028A256
Person / Time
Site:	Surry
Issue date:	01/23/2014
From:	Lane N Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
13-237A
Download: ML14028A256 (4)

Text

VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 January 23, 2014 U. S. Nuclear Regulatory Commission Serial No.: 13-237A Attention: Document Control Desk SPS-LIC/CGL: RO Washington, DC 20555-0001 Docket Nos.: 50-281 License Nos.: DPR-37 VIRGINIA ELECTRIC AND POWER COMPANY SURRY POWER STATION UNIT 2 RESPONSE TO REQUEST FOR CLARIFYING INFORMATION REGARDING STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT FOR THE FALL 2012 REFUELING OUTAGE In a letter dated May 10, 2013 (Serial No.13-237), Virginia Electric and Power Company (Dominion) submitted information summarizing the results of steam generator (SG) tube inspections performed at Surry Power Station Unit 2 during the Fall 2012 refueling outage. In a September 17, 2013 e-mail from Ms. Karen Cotton Gross (NRC Project Manager) to Mr. Gary D. Miller (Dominion Corporate Licensing), the NRC staff requested clarifying information related to the SG inspections.

On January 13, 2014, an NRC - Dominion conference call was held to discuss the Dominion responses previously provided to the NRC. The NRC's questions and Dominion's responses are provided in the attachment to this letter.

If you have further questions or require additional information, please contact Ms. Candee Lovett at (757) 365-2178.

Sincerely, i) 1*'

N. L. Lane Site Vice President Surry Power Station Commitments contained in this letter: None

Attachment:

Response to NRC Request for Clarifying Information Regarding Fall 2012 Steam Generator Inservice Inspection Report - Surry Power Station Unit 2

Serial No. 13-237A Docket Nos. 50-281 Response to Request for Clarifying Information Regarding Unit 2 Fall 2012 SG Inservice Inspection Report Page 2 of 2 cc: U.S. Nuclear Regulatory Commission - Region II Marquis One Tower 245 Peachtree Center Avenue, NE Suite 1200 Atlanta, GA 30303-1257 Ms. K. R. Cotton Gross NRC Project Manager Surry U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738 Dr. V. Sreenivas NRC Project Manager North Anna U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 G-9A 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Surry Power Station Mr. R. A. Smith Authorized Nuclear Inspector Surry Power Station

Serial No. 13-237A Docket Nos. 50-281 Response to Request for Clarifying Information Regarding Unit 2 Fall 2012 SG Inservice Inspection Report Attachment Response to NRC Request for Clarifying Information Regarding Fall 2012 Steam Generator Inservice Inspection Report -

Surry Power Station Unit 2 Virginia Electric and Power Company (Dominion)

Serial No. 13-237A Docket Nos. 50-281 Response to Request for Clarifying Information Regarding Unit 2 Fall 2012 SG Inservice Inspection Report Page 1 of 1 NRC Question 1 The report dated May 10, 2013, states that this was the second inspection in the 4 th inspection period and that the steam generatorshad operated for 301.8 effective full power months (EFPMs). The first, second, and third sequential inspection periods are

'120, 96, and 72 EFPMs with the first sequential inspection period beginning after the first inservice inspection. Assuming the first inspection took place after 13 EFPMs, this would mean that the steam generators have operated at least 301 EFPM. If this was the 2 nd inspection in the fourth sequential period, it would mean that 2 inspections were performed in a 0.8 EFPM interval. Please discuss how the current inspection period was determined.

Dominion Response The NRC question states that the first, second, and third inspection periods are 120 EFPM, 90 EFPM, and 72 EFPM, respectively. These inspection period durations are the current TS 6.4.Q.4.b requirements, which became effective on March 20, 2013 when TS Amendments 278/278 were implemented. TS Amendments 278/278 approved SG Program revisions in accordance with TSTF-510 Revision 2. Our request to adopt the TSTF-510 Program revisions was transmitted by letter Serial No.12-487, dated July 31, 2012, and TS Amendments 278/278 were issued on January 28, 2013.

Prior to the implementation of TS Amendments 278/278, the inspection period durations required by TS 6.4.Q.4.b for the first, second, and third inspection periods were 120 EFPM, 90 EFPM, and 60 EFPM, respectively. The SG inspections conducted during the Unit 2 Fall 2012 were the second of four scheduled for the 4 th inspection period, which was 60 EFPM. The shortest period between inspections for Unit 2 was 12.94 EFPM. Based on this clarification of the inspection period durations, the 301.8 EFPM value (since the first inservice inspection) is verified to be correct.

NRC Question 2 Please discuss the extent of the inspection and analysis of the array probe data collected within the tubesheet/expansion transitionregion.

Dominion Response During the Unit 2 Fall 2012 refueling outage, 100 percent of the tubes in both the hot leg and cold leg in SG "A" was examined with the array probe from either the baffle plate or the tube support plate to the tube end. Analysis excluded the area below the H-star depth of 17.89 inches in accordance with the alternate tube plugging criteria reflected in TS 6.4.Q.3.b. No issues were identified through the tubesheet/expansion transition region to the H-star depth.