ML071930392

Electronic Transmission, Draft Request for Additional Information Regarding the Emergency Diesel Generator Testing Technical Specification Amendments

ML071930392
Person / Time
Site:	Limerick
Issue date:	07/12/2007
From:	Peter Bamford NRC/NRR/ADRO/DORL/LPLI-2
To:	Chernoff H NRC/NRR/ADRO/DORL/LPLI-2
Bamford, Peter J., NRR/DORL 415-2833
References
TAC MD3710, TAC MD3711
Download: ML071930392 (3)

Text

July 12, 2007 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: Peter Bamford, Project Manager /ra/

Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

LIMERICK GENERATING STATION, UNITS 1 AND 2 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING THE EMERGENCY DIESEL GENERATOR TESTING TECHNICAL SPECIFICATION AMENDMENTS (TAC NOS. MD3710 AND MD3711)

The attached draft request for additional information (RAI) was transmitted by electronic transmission on July 12, 2007, to Mr. Glenn Stewart, at Exelon Generation Company, LLC (Exelon). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call (if needed) with Exelon in order to clarify one item in the licensees submittal. The draft RAI is related to Exelons submittal dated November 27, 2006, regarding Limerick Generating Station, Units 1 and 2, emergency diesel generator (EDG) Technical Specifications (TSs). The draft question was sent to ensure that the question was understandable, the regulatory basis was clear, and to determine if the information was previously docketed. Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.

Docket Nos. 50-352 and 50-353

Enclosure:

As stated

July 12, 2007 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM: Peter Bamford, Project Manager /ra/

Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUBJECT:

LIMERICK GENERATING STATION, UNITS 1 AND 2 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING THE EMERGENCY DIESEL GENERATOR TESTING TECHNICAL SPECIFICATION AMENDMENTS (TAC NOS. MD3710 AND MD3711)

The attached draft request for additional information (RAI) was transmitted by electronic transmission on July 12, 2007, to Mr. Glenn Stewart, at Exelon Generation Company, LLC (Exelon). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call (if needed) with Exelon in order to clarify one item in the licensees submittal. The draft RAI is related to Exelons submittal dated November 27, 2006, regarding Limerick Generating Station, Units 1 and 2, emergency diesel generator (EDG) Technical Specifications (TSs). The draft question was sent to ensure that the question was understandable, the regulatory basis was clear, and to determine if the information was previously docketed. Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.

Docket Nos. 50-352 and 50-353

Enclosure:

As stated DISTRIBUTION:

Public RidsNrrPMPBamford LPL1-2 R/F MMcConnell, NRR Accession No.: ML071930392 *via memorandum OFFICE LPL1-2/PM EEEB/BC NAME PBamford GWilson*

DATE 07/12/2007 07/11/2007 OFFICIAL RECORD COPY

DRAFT REQUEST FOR ADDITIONAL INFORMATION LIMERICK UNITS 1 AND 2 EMERGENCY DIESEL GENERATOR TESTING REQUIREMENTS TECHNICAL SPECIFICATION AMENDMENT TAC NOS. MD3710 AND MD3711 DOCKET NOS. 50-352 AND 50-353 By letter dated November 27, 2006, Agencywide Documents Access and Management System (ADAMS) Accession No. ML063310230, Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request regarding the technical specifications (TSs) for Limerick Generating Station (LGS), Units 1 and 2. The proposed changes would modify the TS testing requirements for the emergency diesel generators (EDGs). Based on the review of the information provided by the licensee, the staff has the following additional question.

Page 9 of Attachment 1 of the November 27, 2006, submittal states the following:

Consistent with RG [Regulatory Guide] 1.9, the 1.8 seconds specified is equal to 60% of the 3-second load sequence interval associated with sequencing the next load following the RHR

[residual heat removal] pumps in response to an undervoltage on the electrical bus concurrent with a LOCA [loss of coolant accident]. The change is acceptable because, based on RG 1.9 recommendations, it provides assurance that EDG [emergency diesel generator] frequency does not exceed predetermined limits and that frequency stability is sufficient to support proper load sequencing following a rejection of the largest single load.

Furthermore, page 13 of Attachment 1 of the November 27, 2006, submittal lists RG 1.9, Revision 2 as a reference.

Is it your intent to fully commit to RG 1.9, Revision 2? If so, clearly indicate your intent in writing. If not, provide a detailed technical justification for relaxing the acceptance criteria currently contained in your technical specifications for the EDG load rejection test.

ENCLOSURE