ML19268A042

Pre-Application Meeting License Amendment Request Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b

ML19268A042
Person / Time
Site:	Prairie Island
Issue date:	09/26/2019
From:	Xcel Energy
To:	Office of Nuclear Reactor Regulation
Kuntz R
References
Download: ML19268A042 (17)

Text

Prairie Island Nuclear Generating Plant Pre-Application Meeting License Amendment Request Revise Technical Specifications to Adopt Risk Informed Completion Times TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initiative 4b September 26, 2019

Meeting Agenda

• Describe future license amendment request

- Scope of the request

- Variations from TSTF-505

- PRA Models and CRMP Summary

• Schedule 2

Scope of the Request

• Based on TSTF-505, Revision 2, and NEI 06-09, Risk-Informed Technical Specifications Initiative 4b, Risk-Managed Technical Specifications (RMTS) Guidelines

• RICTs apply to 18 PINGP LCOs

- Applicable in Modes 1 and 2

- No loss of function consistent with template

• New TS 5.5 program called the Risk Informed Completion Time Program

• Precedent approved and under review considered 3

Variations

• Differences in Condition/RA wording

- PINGP TS are based on Revision 1 of NUREG-1431, Standard Technical Specifications Westinghouse Plants

• PINGP plant-specific Conditions/RAs not in TSTF-505

• TSTF-505 Conditions/RAs not applicable to PINGP

• Administrative changes

- TS formatting changes

• Cross-reference list for TSTF-505 markups to PINGP site-specific TS RAs provided

• Re-typed/clean TS pages not included 4

TS 3.3.1 - Reactor Trip System (RTS)

Instrumentation

• Condition not in TSTF-505

- TS 3.3.1.L.1 - for one or both channel(s) inoperable on one bus, place channel(s) in trip

• Bus undervoltage and underfrequency reactor trip function

- 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> CT front stop

- Function is modeled in PRA

- RICT added to RA consistent with TSTF-505 changes 5

TS 3.3.2 - Engineered Safety Feature System (ESFAS) Instrumentation

• Condition not in TSTF-505

- TS 3.3.2.I.1 - for one or both channel(s) inoperable on one bus, place channel(s) in trip

• Bus undervoltage AFW start function

- 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> CT front stop

- Function is modeled in PRA

- RICT added to RA consistent with TSTF-505 changes 6

TS 3.6.5 - Containment Spray and Cooling Systems

• PINGP has two trains of Containment Cooling and both trains are required to be operable by TS LCO 3.6.5.

• Conditions not in TSTF-505

- TS 3.6.5.C.1 - one or both containment cooling FCU(s) in one train inoperable, restore containment cooling FCU(s) to OPERABLE status

- TS 3.6.5.D.2 - one containment cooling FCU in each train inoperable, restore all FCUs to OPERABLE status

- 7 day CT front stops

- FCUs are not modeled in PRA

• Analysis has shown FCUs are not required to prevent a Large Early Release

- RICT added to RAs consistent with TSTF-505 changes 7

TS 3.7.1 - Main Steam Safety Valves (MSSVs)

• TS 3.7.1 LCO requires PINGP to have five MSSVs per steam generator operable or the unit is required to shut down

• Condition not in TSTF-505

- TS 3.7.1.A.1 - for one MSSV inoperable, restore inoperable MSSV to OPERABLE status

- 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> CT front stop

- MSSVs are modeled in PRA

- RICT added to RAs consistent with TSTF-505 changes 8

TS 3.7.8 - Cooling Water (CL) System

• CL is a shared system between PINGP units. TS 3.7.8 LCO requires PINGP to have two CL trains OPERABLE or both units are required to shut down

• Conditions not in TSTF-505

- TS 3.7.8.A.1 - for no safeguards CL pumps OPERABLE for one train, restore one safeguards CL pump to OPERABLE status

• Remove NOTE 3 which limits the Condition existing for greater than 7 days in any consecutive 30 day period

• 7 day CT front stop

- TS 3.7.8.B.3 - for one CL supply header inoperable, restore CL supply header to OPERABLE status

• 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> CT front stop

- CL System modeled in PRA

- RICT added to RAs consistent with TSTF-505 changes 9

PRA Technical Adequacy

• Internal Events including Internal Flooding

- RG 1.200 peer reviewed

- Appendix X to NEI 05-04 finding closure review complete

- One open F&O related to Abeyance RCP seal

• Fire

- RG 1.200 peer reviewed

- Appendix X to NEI 05-04 finding closure review complete

- No open Fire PRA F&Os

- Fire PRA reflects future state of the as-built/as-operated plant following NFPA 805 modifications

• Unit 1 - Fall 2020 RFO; Unit 2 - Fall 2019 RFO

• RICT Program will not be used until modifications are complete on both units and PRA models updated 10

PRA Technical Adequacy (continued)

• Seismic

- No PINGP seismic PRA

- NRC staff assessment of PINGP seismic (ML15341A162):

• Seismic hazard bounded by existing design-basis SSE,

• Therefore, seismic risk evaluation not merited

- Seismic penalty will be applied to all RICTs based on current seismic hazard for CDF & LERF

• Other External Hazards

- Bounding analysis concludes that other external hazards can be screened out from calculations in the RICT Program 11

RICT Program Real-Time Risk Model

• A Real-Time Risk Model similar to existing Maintenance Rule a(4)

Configuration Risk Management Program

- Uses EPRI Phoenix Risk Analysis Software

- Incorporates RICT/RMAT calculation features

- Incorporates seismic penalty factor 12

Impact of Ongoing NRC/Industry Risk-Informed Activities

• Development of an alternative to the administrative TS addressing use of newly developed PRA methods

- Intend to supplement PINGP application if becomes available while PINGP application is under review 13

Schedule

• Projected submission in November 2019 with a requested issuance of December 2020

• Request an implementation period of 180 days 14

Acronyms

• AFW - Auxiliary Feedwater

• CDF - Core Damage Frequency

• CT - Completion Time

• CRMP - Configuration Risk Management Program

• F&O - Facts and Observations

• FCU - Fan Coil Unit

• LAR - License Amendment Request

• LCO - Limiting Condition of Operation

• NEI - Nuclear Energy Institute

• PINGP - Prairie Island Nuclear Generating Plant

• PRA - Probabilistic Risk Assessment 15

Acronyms (continued)

• RA - Required Action

• RCP - Reactor Coolant Pump

• RFO - Refueling Outage

• RICT - Risk Informed Completion Time

• RMA - Risk Management

• RMAT - Risk Management Action Time

• SE - Safety Evaluation

• SSE - Safe Shutdown Earthquake

• TS - Technical Specification

• TSTF - Technical Specification Task Force 16