ML16237A241

TSTF-505 LAR - Exelon Pre-Submittal Meeting Slides

ML16237A241
Person / Time
Site:	Limerick
Issue date:	08/24/2016
From:	Stewart G Exelon Generation Co
To:	Richard Ennis Plant Licensing Branch 1
Ennis R
References
CAC MF8267, CAC MF8268
Download: ML16237A241 (25)

Text

Limerick/NRC Pre-Submittal Meeting Risk Informed Completion Times TSTF-505 License Amendment Request August 30, 2016

Agenda

• Introduction

• License Amendment Request

• PRA Models and CRMP Summary

• Implementation

• Closing Remarks 2

Introduction

• Desired Meeting Outcomes

- Discuss license amendment content

- Identify variances from TSTF-505

- Provide overview of Configuration Risk and PRA models

- Provide overview of implementation activities

- Validate timeline for September 2016 submittal 3

License Amendment Request

• Based on TSTF-505 and NEI 06-09

• 24 LCOs (Modes 1 and 2 only)

• New TS Section 6.0 Program

• Variances from TSTF-505

-LGS TS are old BWR STS; not ITS

-Subtle differences in Condition/RA wording

-TSTF-505 LCOs/Conditions not in LGS TS

-RICT added to plant-specific LCOs not in TSTF-505

-Typed TS pages not included 4

LGS TS 3.1.5 - Standby Liquid Control (SLC)

System

• Condition not in TSTF-505 or NUREG-1433 (BWR ITS)

-TS 3.1.5.b - Standby Liquid Control System otherwise inoperable (vs. two subsystems inoperable)

• Administrative deviation

• SLC is modeled in PRA

• RICT added to each respective Required Action

-Consistent with similar TSTF-505 changes 5

LGS TS 3.3.1 - Reactor Protection System (RPS)

Instrumentation

• Condition not in TSTF-505 or NUREG-1433

-TS 3.3.1.a - Number of inoperable channels in either trip system for one or more Functional Units less than the minimum required operable channels per trip system

• Includes a 1-hour AOT

• RPS is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 6

LGS TS 3.3.3 - Emergency Core Cooling System (ECCS) Instrumentation

• Conditions not in TSTF-505 or NUREG-1433

-TS 3.3.3.c.1 - Either ADS trip system inoperable (with HPCI and RCIC systems operable)

• Restoration action with 7-day AOT

-TS 3.3.3.c.2 - Either ADS trip system inoperable (with HPCI or RCIC systems inoperable)

• Restoration action with 72-hour AOT

• ECCS is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 7

LGS TS 3.3.4.2 - End-of-Cycle Recirculation Pump Trip (EOC-RPT) Instrumentation

• Condition not in TSTF-505 or NUREG-1433

-TS 3.3.4.2.c.1 - Number of OPERABLE channels two or more less than required consisting of one turbine control valve channel and one turbine stop valve channel

• Restoration action with 12-hour AOT

• EOC-RPT is not currently modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 8

LGS TS 3.3.4.1 - Anticipated Trip Without Scram Recirculation Pump Trip (ATWS-RPT)

Instrumentation

• Condition not in TSTF-505 or NUREG-1433

-TS 3.3.4.1.c.1 - Number of OPERABLE channels two or more less than required consisting of one reactor vessel water level channel and one reactor vessel pressure channel

• Restoration action with 12-hour AOT

• ATWS-RPT is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 9

LGS TS 3.3.2 - Primary Containment Isolation Instrumentation

• Conditions not in TSTF-505 or NUREG-1433

-TS 3.3.2.b.1 - OPERABLE channels less than the Minimum OPERABLE Channels per Trip System (tripped condition would cause an isolation)

• Restoration action with 6-hour AOT

-TS 3.3.2.c - OPERABLE channels less than the Minimum OPERABLE Channels per Trip System for both trip systems

• Restoration action with 1-hour AOT

• PCI is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 10

LGS TS 3.5.1 - ECCS - Operating

• Condition not in TSTF-505 or NUREG-1433

-TS 3.5.1.b.5 - Three LPCI subsystems inoperable with both Core Spray subsystems operable

• Restoration action with 72-hour AOT

• ECCS is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 11

LGS TS 3.6.1.3 - Primary Containment Air Lock

• Condition not in TSTF-505 or NUREG-1433

-TS 3.6.1.3.a.1 - One air lock door inoperable

• Restoration action with 24-hour AOT

• Air lock is not currently modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 12

LGS TS 3.7.1.1 - Residual Heat Removal Service Water (RHRSW) System

• Conditions not in TSTF-505 or NUREG-1433

-TS 3.7.1.1.a.3.a) and a.3.b) - Allows the 72-hour allowed outage time (AOT) for the RHRSW system to be extended up to 7 days during repairs of the RHRSW subsystem piping

-Also affects TS 3.6.2.3 - Suppression Pool Cooling mode of RHR, TS 3.7.1.2 - Emergency Service Water and TS 3.8.1.1 - A.C. Sources -Operating [Emergency Diesel Generators]

• Affected systems are modeled in PRA

• RICT added to Required Actions and footnotes

• Only change is a calculated RICT 13

LGS TS 3.7.1.1 - Residual Heat Removal Service Water (RHRSW) System

• Conditions not in TSTF-505 or NUREG-1433

-TS 3.7.1.1.a.6 - Three RHRSW pump/diesel generator pairs inoperable

• Restoration action with 7-day AOT

-TS 3.7.1.1.a.7 - Four RHRSW pump/diesel generator pairs inoperable

• Restoration action with 8-hour AOT

• RHRSW is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 14

LGS TS 3.7.1.2 - Emergency Service Water (ESW) System

• Conditions not in TSTF-505 or NUREG-1433

-TS 3.7.1.2.a.4 - Three ESW pump/diesel generator pairs inoperable

• Restoration action with 72-hour AOT

-TS 3.7.1.2.a.5 - Four ESW pump/diesel generator pairs inoperable

• Restoration action with 8-hour AOT

• ESW is modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 15

LGS TS 3.8.1.1 - AC Sources - Operating

• Condition not in TSTF-505 or NUREG-1433

-TS 3.8.1.1.e.1 - Two train systems, with one or more diesel generators inoperable

• Restoration action with 72-hour AOT

• EDGs are modeled in PRA

• RICT added to Required Action

-Consistent with similar TSTF-505 changes 16

PRA Models and Configuration Risk Management Program (CRMP)

• PRA models updated/upgraded and peer-reviewed

• F&O closure independently validated

• Updated screening for RG 1.200, Rev. 2 hazards

• Total CDF/LERF meet RG 1.174, Rev. 2 criteria 17

Internal Events PRA

• BWROG Internal Events Peer Review October 2005; PRA Standard Part 2

• Focused scope BWROG review for internal flooding May 2008; PRA Standard Part 3

• Gap Assessment performed relative to RG 1.200, Rev. 2

• Most Supporting Requirements (SRs) assessed as PRA Standard Capability Category II

-Majority of unresolved peer review findings related to documentation

-Most Findings addressed in latest internal events PRA model update

-SRs met at Capability Category II after resolution of findings

-No significant impact on CDF or LERF 18

Internal Fire PRA

• Peer review by BWROG in November 2011; PRA Standard Part 4 (Internal Fire) and RG 1.200, Rev.

2 following NEI 07-09 peer process

• Most Supporting Requirements judged to meet Capability Category II

-Majority of findings addressed in latest Fire PRA model update 19

Peer Review Findings Closure Review

• Formal process by Independent review team

-Assessed disposition of Findings for Internal Events and Internal Fire PRAs

-Observed by NRC

-Confirmed resolution of most Findings, resulting in SRs Met/Capability Category II

-Identified several areas for additional assessment relative to specific applications

• Will be addressed in the LAR assessment of Technical Adequacy 20

Other Hazards

• Seismic

-No Current Limerick Seismic PRA

• Limerick is a relatively low seismic hazard site

• NRC Staff Assessment of Limerick (ML15296A492):

- Re-evaluated hazard bounded by SSE in frequency range of 1 to 10 Hz

- Therefore, seismic risk evaluation not merited

-Seismic penalty will be applied to all RICTs based on

• Current seismic hazard (EPRI 2013)

• Limiting plant level HCLPF based on IPEEE

• Other

-Updated IPEEE screening evaluation performed

-No other external hazards required to be included in the RICT calculations 21

RICT CRMP Model

• Real-time risk model as currently used for existing Maintenance Rule a4 CRM

• Uses PARAGON software

• Incorporates RICT/RMAT calculation features

• Handles multiple overlapping configurations

• Developed with operator input 22

Implementation

• Operations owns implementation

• Cross-functional team supporting implementation

• RICT implemented in Modes 1 and 2 only

• CRMP and PRA Models updated to support RICT

• Procedure changes and training

• Site-wide Communications 23

Procedures and Training

• Procedures

-Revised to address risk management action times, PRA functionality, and incremental risk tracking

-New RICT Program Procedure

• Level 1 Training

-Hands-on (detailed) training for Operators and Work Management

-Classroom training to address how RICT impacts Station Operations

-Integrated with current online processes

• Level 2 Training

-Support training for managers on process, expectations, limitations

• Level 3 Training 24

-Awareness training for all others

Closing Remarks

• Next Steps

-Submit the LAR in September 2016

-Refine implementing procedures

-Conduct training in 2016/2017

-Ready to implement in 2017

-Submit 50.69 using generic template

• Questions 25