ML14127A462

Request for Additional Information Regarding License Amendment Request to Modify Specification 3.8.4 Setpoint

ML14127A462
Person / Time
Site:	McGuire, Mcguire
Issue date:	05/12/2014
From:	Geoffrey Miller Plant Licensing Branch II
To:	Capps S Duke Energy Carolinas
Miller G
References
TAC MF2983, TAC MF2984
Download: ML14127A462 (3)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Steven D. Capps Vice President McGuire Nuclear Station Duke Energy Carolinas, LLC 12700 Hagers Ferry Road Huntersville, NC 28078-8985 May 12, 2014

SUBJECT:

MCGUIRE NUCLEAR STATION, UNITS 1 AND 2: REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST TO MODIFY TECHNICAL SPECIFICATION 3.8.4 SETPOINT (TAC NOS. MF2983 AND MF2984)

Dear Mr. Capps:

By letter dated October 28, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13304B445), Duke Energy Carolinas, LLC (the licensee) submitted a license amendment request, which requested to modify Technical Specification 3.8.4, "DC Sources-Operating." Specifically, the proposed change would allow a one-time extension of the completion time for required action A.2.2 to support battery replacement.

The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensee's submittal and determined that additional information is needed in order to complete our review. The.:

enclosed document describes this request for additional information (RAI). On May 6, 2014, the Duke staff indicated that a response to the RAI would be provided by June 6, 2014.

• If you have any questions, please call me at 301-415-2481.

Docket Nos. 50-369 and 50-370

Enclosure:

Request for Additional Information cc w/encl: Distribution via Listserv G. Edward Miller, Project Manager Plant Licensing Branch 11-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

REQUEST FOR ADDITIONAL INFORMATION MCGUIRE NUCLEAR STATION, UNITS 1 AND 2 PROPOSED CHANGES TO TECHNICAL SPECIFICATION 3.8.4 ONE-TIME EXTENSION OF REQUIRED ACTION A.2.2 COMPLETION TIME DOCKET NOS. 50-369 AND 50-370 By letter dated October 28, 2013, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML133048445), Duke Energy Carolinas (Duke) submitted a license

• amendment request (LAR) to amend the Technical Specifications (TS) 3.8.4, "DC Sources-Operating," for McGuire Nuclear Station, Units 1 and 2, in support of plant modifications to replace existing shared vital batteries while at power. In order for the NRC staff to complete its review of the LAR, the following additional information is requested.

1. On page 2 of Attachment 1 of the LAR, the licensee stated that about 50% of the vital batteries cells are affected by positive post seal nut and jar lid cracking. Please discuss available mitigation strategies/further maintenance that will be used on the new batteries to prevent this potential failure mechanism.

2. On page 8 of Attachment 1 of the LAR, the licensee stated that the new vital batteries are essentially the same as the existing batteries with the exception of the new ones being rated 1944 ampere hours instead of 1945 ampere hours at the 8-hour discharge.

Please explain why reducing the ampere hours rating does not impact the existing design/licensing basis margins for DC power system.

3. On page 1 0 of Attachment 1 of the LAR, the licensee stated that a temporary charger will be installed to maintain the temporary battery at 132 volts DC. The temporary charger will have a disconnect to electrically isolate it from the temporary battery and the DC bus. Describe the design and capability of the temporary battery charger, including how it will be connected to a Class 1 E supply, if needed. Also, please explain whether the temporary battery charger will impact the emergency diesel generator loading.

Enclosure

ML14127A462 OFFICE NRR/LPL2-1/PM NRR/LPL2-1 /LA NRR/DE/EEEB/BC NAME GEM iller SFigueroa JZimmerman DATE 05/12/14 05/12/14 04/22/14