ML120370496

Email, Request for Additonal Information, License Amendment Request to Revise TS 3.7.1, Main Steam Safety Valves

ML120370496
Person / Time
Site:	Diablo Canyon
Issue date:	02/06/2012
From:	Steven Lynch Plant Licensing Branch IV
To:	Soenen P Pacific Gas & Electric Co
lynch steven, nrr/dpr, 415-1524
References
TAC ME5713, TAC ME5714
Download: ML120370496 (1)

Text

From: Lynch, Steven Sent: Monday, February 06, 2012 3:05 PM To: Soenen, Philippe R Cc: Wang, Alan; Sebrosky, Joseph; Gardocki, Stanley; Gall, Jennifer; Lent, Susan; Burkhardt, Janet

Subject:

RAI for DCPP Requested Revision to TS 3.7.1, "Main Steam Safety Valves (MSSVs)" (TAC Nos. ME5713 and ME 5714)

Philippe, By letter dated February 17, 2011 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML110480870), Pacific Gas and Electric Company (PG&E) submitted PG&E Letter DCL-11-018, License Amendment Request 11-02, Revision to Technical Specification 3.7.1, Main Steam Safety Valves (MSSVs). This request was later supplemented by letter dated April 21, 2011.

PG&E submitted a request for revision to Facility Operating License Nos. DPR-80 and DPR-82, revising Technical Specification (TS) 3.7.1, Main Steam Safety Valves (MSSVs), Table 3.7.1-1, Maximum Allowable Power Range Neutron Flux High Setpoint with Inoperable MSSVs, to remove a one-time note specific to DCPP, Unit No. 2 for Cycle 15, which is no longer applicable or needed. The licensee also proposed to revise the TS Bases, applicable to DCPP, Unit Nos. 1 and 2, to adopt a new analysis methodology for establishing the reduced power range neutron flux high setpoint for one inoperable MSSV as listed in TS Table 3.7.1-1. By letter dated April 21, 2011, the licensee clarified that the proposed revision to the TS Bases is a revision to the FSARU Sections 15.2.7.3, Results, and 15.2.16, References.

The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the information provided in your application and determined that the following additional information is required in order to complete its review. This request for additional information (RAI) was discussed with you on February 2, 2011. In a follow-up call on February 6, 2012, it was agreed that a response to this RAI would be provided by February 27, 2012. Should the NRC determine that this RAI is no longer necessary prior to this date, the request will be withdrawn. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1524 or via e-mail at Steven.Lynch@nrc.gov. The NRC staff has determined that no security-related or proprietary information is contained herein.

Request for Additional Information

1. Please provide the basis for the change in the MSSV accumulation initial condition uncertainties from 3% accumulation used in PG&E Calculation N-114, Rev. 0 to 5 psi accumulation used as an input parameter in the new Westinghouse RETRAN-02W analyses.

Regards, Steve Lynch General Engineer

Office of Nuclear Reactor Regulation Division of Operating Reactor Licensing, Plant Licensing Branch 4 Office: O-12F08 MS: O-12D20 Phone: 301-415-1524