ML091831237

Response to Request for Additional Information on EOC-24 Steam Generator Inservice Inspection Summary Report

ML091831237
Person / Time
Site:	Oconee
Issue date:	06/30/2009
From:	Baxter D Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML091831237 (3)

Text

Duke DAVE BAXTER P Energy. Vice President Oconee Nuclear Station Duke Energy ON01 VP / 7800 Rochester Highway Seneca, SC 29672 June 30, 2009 864-873-4460 864-873-4208 fax dabaxter@dukeenergy.com U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-001

Subject:

Duke Energy Carolinas, LLC Oconee Nuclear Station, Unit 1 Docket Nos. 50-269 Unit 1 EOC-24 Refueling Outage, Steam Generator Inservice Inspection Request for Additional Information Response By letter dated August 28, 2008, Duke submitted Unit 1 end-of-cycle (EOC) Steam Generator (SG) Inservice Inspection Summary Report, per American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, Subsubarticles IWA-6230 and IWA-6240.

On May 28, 2009, Duke received a request for additional information (RAT) via email from the NRC Staff concerning the Unit 1 EOC-24 SG Summary Report duke submitted on August 28, 2008. This submittal, is to address the staffs questions posed in the RAI. The following attachment contains the reviewer's questions, and Duke's responses to each.

If there are any question or further information needed -you'may contact Corey Gray at (864) 873-6325.

Sincerely, Day Baxter Site Vice President Attachment AW-7.

www. duke-energy.corn

U.S. Nuclear Regulatory Commission June 27, 2009 Page 2 xc w/att: Mr. Luis Reyes Region II Administrator U.S. Nuclear Regulatory Commission Atlanta Federal Center 61 Forsyth St., SWW, Suite 23T85 Atlanta, Ga 30303 Mr. John Stang Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555 xc (w/o att): Mr. Eric Riggs Senior NRC Resident Inspector Oconee Nuclear Station Mrs. Susan Jenkins Section Manager Division of Waste Management Bureau of Land and Waste Management SC Dept. of Health & Environmental Control 2600 Bull St.

Columbia, SC 29201

Response to REQUEST FOR ADDITIONAL INFORMATION OCONEE NUCLEAR STATION. UNIT 1 2008 STEAM GENERATOR TUBE INSPECTIONS TAC No. ME0457 DOCKET No. 50-269

1. Please discuss the scope and results of any secondary side steam generator inspections.

Duke Response No secondary side inspections were performed.

2. Please clarify the scope of your steam generator tube inspections. In particular, clarify the statement that 100% of the tubes were inspected "composing of approximately 50%

of the tubes each with the bobbin and x-probe."

Duke Response 100% of in-service tubes were inspected with bobbin probe. Approximately 50% of those bobbin inspections were performed with a combination probe (bobbin & array) called an X-probe. The remaining inspections (approximately 50%) were performed with a standard bobbin probe.

3. You indicated that twelve tubes were plugged in steam generator A and nine tubes were plugged in steam generator B. Please confirm that the tubes that were plugged can be identified by the code "LAR" in the "util3" field.

Duke Response There is a requirement in the data management close-out checklist for the lead analyst to review (LAR) all 40% TW and greater calls. The LAR code is not a requirement for tubes to be plugged.

4. You indicated that "condition monitoring structural integrity was demonstrated." Please confirm that you maintained accident induce leakage integrity during the cycle preceding the 2008 inspections.

Duke Response Accident induced leakage integrity was also maintained during the last cycle.