ML072980664

Meeting Presentation on Update on Generic Safety Issue 191 Plant Audits

ML072980664
Person / Time
Site:	Millstone, Salem, Oconee, Indian Point, Saint Lucie, Watts Bar, Prairie Island, North Anna, Waterford, San Onofre
Issue date:	10/24/2007
From:	Michael Scott Office of Nuclear Reactor Regulation
To:
References
GL-04-002, GSI-191
Download: ML072980664 (10)

Text

Update on Generic Safety Issue 191 Plant Audits Presented by:

Michael Scott Office of Nuclear Reactor Regulation Presented to: Public Meeting on GSI-191 October 24, 2007 1

Purpose of Presentation

• Briefly summarize audit process

• Discuss results to date

• Discuss future plans 2

Audit Purposes

• Increase effectiveness and efficiency of NRC and industry efforts to address Generic Letter (GL) 2004-02 by:

- promoting more timely issue resolution

- promoting uniform treatment of issues

- identifying issues early to promote consistent responses and stable regulatory environment 3

Selection Criteria and Audit Plans

• Approximately 10 audits to be conducted

- all scheduled, in progress, or complete (status follows)

• Emphasis is on adequacy of design and supporting analyses 4

GSI-191 Audits Plant Site Visit Report Status Watts Bar March 2006 Complete San Onofre Aug/Sep 2006 Complete Prairie Island October 2006 Complete Millstone January 2007 Complete Oconee March 2007 Complete Waterford June 2007 Nearly complete North Anna July 2007 In progress Salem October 2007 In progress Indian Point December 2007 St Lucie January 2008 5

Process

• Documents requested in advance

• Snapshot of completion status

• Usually 1 week or less onsite, 7-8 auditors

• Usually no requests for additional information (RAIs)

• Product is an audit report

• Draft open items to be visible soon after audit as publicly available memo - see PWR Sump Performance web page

• Open items to be addressed by licensees in 12/31/07 GL 2004-02 responses (or by supplement, for last audits)

• Reports to be public (after affected licensees and contractors verify nonproprietary) on NRCs sump website Note: Inspection of installation of modifications at each plant not within scope (TI-2515/166) 6

Audit Results

• As expected, a number of open items identified in each audit to date

• Recent audits indicate affected licensees aware of issues at other plants and addressing them

• List of recent example issues follows - not all-inclusive 7

Issues Identified (1 or more plants)

• Chemical effects still not addressed

• In-vessel and ex-vessel downstream effects not fully addressed

• Nonprototypical debris preparation for head loss testing

• Weak justification for choice of surrogate debris

• LPSI pump failure to stop 8

Issues Identified (Continued)

• No evaluation of potential for vapor flashing

• Some upstream water holdup mechanisms not considered

• Head loss scaling for parameters other than temperature

• Inadequate basis for assumptions regarding time-dependent debris arrival 9

What do results show?

• Progress has been made

• Some areas not demonstrated to be close to successful completion

• Licensee Generic Letter 2004-02 submittals need to provide confidence issues such as those noted have been addressed

• Staff plans limited-scope audits in 2008 to address chemical and downstream effects 10