ML20149K333

Final ASP Analysis - Fitzpatrick (LER 333-82-009)

ML20149K333
Person / Time
Site:	FitzPatrick
Issue date:	05/28/2020
From:	Christopher Hunter NRC/RES/DRA/PRB
To:
Littlejohn J (301) 415-0428
References
LER 1982-009-00
Download: ML20149K333 (1)

Text

LER 333/82-009 Event

Description:

Reactor Trip with High-Pressure Coolant Injection System Inoperable Date of Event: February 23, 1982 through March 9, 1982 Plant: Fitzpatrick Summary On February 10, 1982 during shutdown for refueling, it was discovered that the high-pressure coolant injection (HPCI) system high steam flow set point in the plant Technical Specifications was in error. On March 10, a trip occurred. Two days later, the high-pressure coolant injection system isolated during a startup test due to a high steam flow signal.

It is assumed that the HPCI system was unavailable during the trip since it isolated two days after the trip occurred. In the analysis, the HPCI system was therefore assumed unavailable. The non-recovery probability was set equal to 0.55 to reflect the possibility that the failure might be recovered at the pump. The conditional core damage probability estimated for this event is 4.8x10-6. The dominant core damage sequence involves the transient, successful reactor shutdown, failure of the power conversion system, success of main feedwater, and failure of the residual heat removal (RHR) system.