ML20168A557

Final ASP Analysis - Hatch 2 (LER 366-79-059)

ML20168A557
Person / Time
Site:	Hatch
Issue date:	06/16/2020
From:	Christopher Hunter NRC/RES/DRA/PRB
To:
Littlejohn J (301) 415-0428
References
LER 1979-059-00
Download: ML20168A557 (4)

Text

CIC and HPOI Isolate Following a Reactor Scram at Hatch 2 re sequence was:

g a MSIV fast closure test, the reactor tripped (as intended) due to closure.

and RCIC isolated due to a high AIP signal.

perators reset and manually started both systems.

e action:

P switch was out of specs and it was reset.

vestigation was initiated to discern the cause of the out-of-spec tion.

urpose of failed system ur component:

is designed to maintain water level control given a small Loca.

is designed to maintain water level control given a loss of feed-flow.

IPswitches are designed to send an isolation signal given a steamline break in the HPCI or RCIC system.

ility of system per WASH 1400:

• HPCI: 8.8 x*10-2 /D given Loca RCIC: 8.0 x 10 2 /D given Loca ility of component per WASH 1400:

• pressure switches: 10-4 /D vailabilities are in units of per demand D .Failure rates are in per hour HR-1 .

jthen Damage No No - Feedwater system, available as was the AD~S, LPCI/CS system No 150499 - Actual Occurrence of RCIC and HPCI Isolate Following a Reactor Scram at Hatch 2

Core Damage No Yes 2 No 3

&t Yes Yes 6 Yes7 150499 -Sequence of Interest for ROTC and HPCI Isolate Following a Reactor Scram at Hatch 2 ess requires the operator to reset HPCI and/or RCIC.

of feedwater is presumed.

CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS ACCESSION NUMBER: 150499

. OF LER: July 6, 1979 OF EVENT: June 28, 1979 EM INVOLVED: HPCI, RCIC PONENT INVOLVED: AP switches SE: unknown as of reporting date ENCE OF INTEREST: loss of feedwater flow AL OCCURRENCE: RCIC and HPCI isolate followingas reactor scram at Hatch 2 TOR NAMýE: Hatch 2 ET NUMBER: 50-366 TOR TYPE: BWR GN ELECTRICAL RATING: 784 Nwe TOR AGE: 1.0 yr OR: General Electric ITECT-ENGINEERS: Southern Services/Bechtel ATORS: Georgia Power TION: 11 miles N of Baxley, Georgia 36 ATION: 0(a) hours T OPERATING CONDITION: 0% power TY FEATURE TYPE OF FAILURE: (a) inadequate performance; (b) failed to start; (5made inopera ble; (d) ____________

OVERY METHOD: operational test ENT: -