ML061070094

03/16/2006 Summary of Meeting with PG&E Regarding Digital Upgrade Project

ML061070094
Person / Time
Site:	Diablo Canyon
Issue date:	05/01/2006
From:	Wang A Plant Licensing Branch III-2
To:	Terao D Plant Licensing Branch III-2
Wang A
References
TAC MD0385, TAC MD0386
Download: ML061070094 (5)

Text

May 1, 2006MEMORANDUM TO:David Terao, ChiefPlant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor RegulationFROM:Alan B. Wang, Project Manager/RA/Plant Licensing Branch IVDivision of Operating Reactor Licensing Office of Nuclear Reactor Regulation

SUMMARY

OF MARCH 16, 2006, MEETING WITH PACIFIC GAS ANDELECTRIC COMPANY (PG&E) ON DIGITAL UPGRADE PROJECT (TAC NOS. MD0385 and MD0386)On March 16, 2006, the Nuclear Regulatory Commission (NRC) staff conducted a meeting withPG&E to discuss a digital upgrade project for Diablo Canyon Power Plant, Units 1 and 2 (DCPP). This meeting had an open and closed session. PG&E stated that it had proposed this meeting to start a dialog with the NRC staff to discuss itsdigital upgrade project for the DCPP. PG&E wanted to establish some lines of communication with the staff on this future upgrade. Allen Howe stated that the NRC agreed to this meeting togather information about PG&E's digital upgrade project and that no decisions about the scopeor acceptability of the project would be made as a result of this meeting.PG&E explained the need for the upgrade and its long-term strategy. PG&E noted that thiswould be a hybrid system for a time during installation. There are too many systems affectedfor them all to be changed in a single outage, and, therefore, there will be a transitional periodwherein some but not all of the new equipment will be installed. There would be some limitedtechnical specification changes required. The amendment for these changes is scheduled to be submitted in July 2007. The replacement is currently scheduled for the fall of 2009 for Unit 2 and 2010 for Unit 1. However, PG&E stated that NRC acceptance of the proposed architectureis needed before detailed design would start. PG&E is investigating various options for accomplishing this NRC review. PG&E is considering submitting a plant-specific TopicalReport or an unreviewed safety question amendment for this purpose. PG&E has proposed to have a technical discussion of the proposed changes onsite this summer when more detail of the digital upgrade project has been defined.

The NRC staff indicated concern over the reduction of protection/control diversity that wouldresult from the proposed use of the same platform design in various protecti on systems andcontrol systems. The NRC staff also noted that the reduction in the variety of system designs,presented as beneficial from a maintenance and economic standpoint, results in reduced diversity. The NRC staff stated, for example, control and protection systems are typically notsubject to common-mode failures, but that the proposed use of the same platform design could introduce the possibility of common-mode failures. Presently, control and protection systemsprotect safety limits individually. If they are combined and are subject to common-mode failures, then they will no longer be able to back each other up. The NRC staff pointed out thatthis reduced diversity could have a negative impact upon the overall level of plant safety. The licensee believes that the consolidation would be benign from a safety standpoint and that thisissue will be addressed in its D3 analysis.The NRC staff thanked the licensee for the presentation and agreed that a followup meetingwould be appropriate. Members of the public were not in attendance. A list of attendees is attached. The non-proprietary presentation slides are available in the Agencywide Documents Access and Management System under accession number ML060860251.

Enclosure:

List of Meeting Attendees cc w/encl: See next page Docket Nos. 50-275 and 50-323 failures, then they will no longer be able to back each other up. The NRC staff pointed out thatthis reduced diversity could have a negative impact upon the overall level of plant safety. The licensee believes that the consolidation would be benign from a safety standpoint and that thisissue will be addressed in its D3 analysis.The NRC staff thanked the licensee for the presentation and agreed that a followup meetingwould be appropriate. Members of the public were not in attendance. A list of attendees is attached. The non-proprietary presentation slides are available in the Agencywide Documents Access and Management System under accession number ML060860251.

Enclosure:

List of Meeting Attendees cc w/encl: See next page Docket Nos. 50-275 and 50-323DISTRIBUTION

PUBLICRidsNrrDeEicb (AHowe)RJasinski LPLIV ReadingPRebstock, NRR/ADESMWaterman, NRR/ADESRidsNrrDorlPLoeser, NRR/ADESBKemper, RESRidsNrrDorlLpl4CDoutt, NRR/ADRASArndt, RESRidsNrrPMAWangJBongara, NRR/ADRORidsOgcRpMChiramal, NRR/ADES RidsAcrsAcnwMailCenterACCESSION NO.: NRC-001OFFICENRR/LPL4/PMNRR/LPL4/LANRR/DE/EICB/BCNRR/LPL4/BCNAMEAWang;mxr4LFeizollahiAHowe (w/edits)DTerao DATE4/28/064/27/064/26/20065/1/06OFFICIAL RECORD COPY ENCLOSUREMEETING WITH PACIFIC GAS AND ELECTRIC (PG&E)LIST OF ATTENDEESMarch 16, 2006PG&EWestinghouseINVENSYSAltranD. JacobsJ. MauckC. Scott T. QuinnT. GrozanL. ErinJ. MurrayT. Harris S. PattersonJ. HeflerNRCA. HoweD. Terao A. Wang M. Waterman P. Loeser B. Kemper S. Arndt C. Doutt P. Rebstock J. Bongara M. Chiramal Diablo Canyon Power Plant, Units 1 and 2 cc:

NRC Resident InspectorDiablo Canyon Power Plant c/o U.S. Nuclear Regulatory Commission

P.O. Box 369 Avila Beach, CA 93424Sierra Club San Lucia ChapterATTN: Andrew Christie P.O. Box 15755 San Luis Obispo, CA 93406Ms. Nancy CulverSan Luis Obispo Mothers for Peace

P.O. Box 164 Pismo Beach, CA 93448ChairmanSan Luis Obispo County Board of Supervisors 1055 Monterey Street, Suite D430 San Luis Obispo, CA 93408Mr. Truman BurnsMr. Robert Kinosian California Public Utilities Commission 505 Van Ness, Room 4102 San Francisco, CA 94102Diablo Canyon Independent Safety Committee ATTN: Robert R. Wellington, Esq. Legal Counsel 857 Cass Street, Suite D Monterey, CA 93940Regional Administrator, Region IVU.S. Nuclear Regulatory Commission Harris Tower & Pavillion 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064Richard F. Locke, Esq.Pacific Gas & Electric Company P.O. Box 7442 San Francisco, CA 94120City EditorThe Tribune 3825 South Higuera Street

P.O. Box 112 San Luis Obispo, CA 93406-0112Director, Radiologic Health BranchState Department of Health Services P.O. Box 997414, MS 7610 Sacramento, CA 95899-7414Mr. James D. Boyd, CommissionerCalifornia Energy Commission 1516 Ninth Street (MS 31)

Sacramento, CA 95814Mr. James R. Becker, Vice PresidentDiablo Canyon Operations and Station Director Diablo Canyon Power Plant

P.O. Box 3 Avila Beach, CA 93424Jennifer TangField Representative United States Senator Barbara Boxer 1700 Montgomery Street, Suite 240 San Francisco, CA 94111Mr. John S. KeenanSenior Vice President - Generation and Chief Nuclear Officer Pacific Gas and Electric Company Diablo Canyon Power Plant P.O. Box 770000, Mail Code B32 San Francisco, CA 94177-0001