ML110620087

Request for Additional Information Regarding RR 10-MN-002, Extension of Volumetric Inspection of Steam Generator Primary Manway Studs for One Operating Cycle Beyond the Third 10-Year Inservice Inspection Interval End Date

ML110620087
Person / Time
Site:	McGuire
Issue date:	03/02/2011
From:	Thompson J H Plant Licensing Branch II
To:	Ashe K L, Phong T Duke Energy Carolinas
Thompson Jon, NRR/DORL/LPL 2-1, 415-1119
References
TAC ME4677
Download: ML110620087 (2)

Text

From: Thompson, Jon Sent: Wednesday, March 02, 2011 4:10 PM To: Ashe, Ken; Vu, Phong T Cc: Kulesa, Gloria; Wallace, Jay

Subject:

Request for Additional Information for Relief Request 10-MN-002 submitted August 30, 2010

SUBJECT:

MCGUIRE NUCLEAR STATION, UNIT 1 (MCGUIRE 1), REQUEST FOR ADDITIONAL INFORMATION (RAI) REGARDING RELIEF REQUEST 10-MN-002, "EXTENSION OF VOLUMETRIC INSPECTION OF STEAM GENERATOR PRIMARY MANWAY STUDS FOR ONE OPERATING CYCLE BEYOND THE THIRD 10-YEAR INSERVICE INSPECTION INTERVAL END DATE" (TAC NO. ME4677)

By letter dated August 30, 2010, Duke Energy Carolinas, LLC (the licensee), submitted a request for relief regarding the extension of the volumetric inspection of steam generator primary manway studs for one operating cycle beyond the third 10-year inservice inspection interval end date for McGuire 1. The U.S. Nuclear Regulatory Commission staff has reviewed the licensee's submittal and determined that an RAI is needed in order to complete our review. The enclosed document describes this RAI. A written response should be provided to the NRC staff for these RAI questions within 30 days in order to support our timely review of this request. Please inform me as soon as possible if you are unable to support this response timeframe.

If you have any questions, please call me at 301-415-1119.

Sincerely, Jon Thompson, Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-369

Enclosure:

As stated

OFFICE OF NUCLEAR REACTOR REGULATION REQUEST FOR ADDITIONAL INFORMATION EXTENSION OF VOLUMETRIC INSPECTION OF STEAM GENERATOR PRIMARY MANWAY STUDS FOR ONE OPERATING CYCLE BEYOND THE THIRD 10-YEAR INSERVICE INSPECTION INTERVAL END DATE DUKE ENERGY CAROLINAS, LLC MCGUIRE NUCLEAR STATION, UNIT 1 DOCKET NO: 50-369 By letter dated August 30, 2010, Duke Energy Carolina, LLC (the licensee) submitted Relief Request Serial # 10-MN-002, "Extension of Volumetric Inspection of Steam Generator Primary Manway Studs for One Operating Cycle Beyond the Third 10-Year Inservice Inspection Interval End Date" (Agencywide Documents Access and Management System Accession No. ML102510185). The Nuclear Regulatory Commission staff needs the following further information in order to complete its review:

1. What is the stud material of construction?

2. What is the gasket material of construction?

3. What is the current stud fatigue cumulative usage factor?

4. If one stud were to fail during full power operation:

a. What is the expected leak rate?

b. Would the leak rate be sufficient to be detectable by the Surveillance Test "Reactor Coolant Leakage Calculation," containment airborne radiation monitors and changing Ventilation Unit Drain Tank level measurements?