ML14120A011

4/29/2014 - South Texas Project Regulatory Approach for Risk-Informed Pilot Submittal Presentation Relating to 10 CFR 50.46c (TAC ME2908)

ML14120A011
Person / Time
Site:	South Texas
Issue date:	04/29/2014
From:	South Texas
To:	Office of Nuclear Reactor Regulation
Inverso, Tara
Shared Package
ML14114A501	List: ML14120A011
References
TAC ME2908
Download: ML14120A011 (4)

Text

STP Regulatory Approach for Risk-InformedPilotSubmittal Risk Informed Pilot SubmittalPbliMti P u bli c M ee ti ng on 10CFR50.46c Draft RuleApril 29, 2014 1

High Level View of the STP Pilot Application

• The licensin g a pproach is based on Re g ulator y Guide 1.174gppgy*Risk quantification is the difference in risk between a "perfect" design where debris effects are assumed to be deterministicallyprecludedandtheexistingdesign deterministically precluded and the existing design*Quantitative acceptance criteria are CDF<1E-6 and LERF<1E-7, as depicted in RG 1.174 Region III

• The inputs to the risk model encompass the concerns raised in GSI-191, including the major topical areas discussed in NEI 04-07asappropriate 07 , as appropriate 2

Scope and Basis for Regulatory Framework*A pp lication is focused onl y on the effects of debris as ppy it relates to long-term cooling

• If the risk due to debris meets the RG 1.174 acceptance criteria, then it is concluded that the long term cooling functions that could be affected by debris will be available to perform their function in p accordance with their existing licensing and design

basis 3 Basic Elements of STP Regulatory Changes*Exemptions proposed for functions supported by strainers:

• ECCS: GDC 35

• ContainmentSpray:GDC38,41 Containment Spray: GDC 38, 41*Core flow: 10CFR50.46(d) "...other requirements..." *ComplementsGDCexemptions

• Complements GDC exemptions

• License Amendment Request for change in methodof analysis

• No TS changes proposed

• UFSAR and TS Bases changes 4