ML20168A555

Final ASP Analysis - Hatch 2 (LER 366-79-045)

ML20168A555
Person / Time
Site:	Hatch
Issue date:	06/16/2020
From:	Christopher Hunter NRC/RES/DRA/PRB
To:
Littlejohn J (301) 415-0428
References
LER 1979-045-00
Download: ML20168A555 (4)

Text

Fails to Start When Turbine Stop Valve Fails to Open at Hatch 2 equence was:

wer ascension the reactor tripped due to a condensate system trip.

ed to initiate on low-low water level due to a failed turbine stop valve.

m HPCI mechanical seal cooling lines was leaking into the bracket drain The bracket drain cavity line had a valve installed for unknown reasons.

e was closed which caused water to back up into the adjacent bearing nd thus contaminate the pump oil.

was out of service for unspecified reasons.

or was placed in hot shutdown using the immediately repaired condensate ion:

ng seal line was replaced.

ystem was drained, flushed and twice refilled.

ne bearing was inspected and found to be undamaged.

in the bracket drain line was locked open and am investigation initiated ine its significance.

of failed system or component:

system is designed to control water level given a small LOCA.

is designed to control water level given a loss of feedwater.

of system per WASH 1400:

• HPCI: 8 .8 x 10-2 /D RCIC: 8.0 x 10- 2 /Dl of component per WASH 1400:* -

bilities are in units of per demand D-1. Failure rates are in our HR? 1 .

ccession due low-low reactor of service densate system which Core o condensate water inventory had been immediately Damage ystem trip due to failed repaired turbine stop valve

- ADS/LPCI & CS available NSIC 149961 - Actual Occurrence for HFCI Fails to Start When Its Turbine Stop Valve Fails to pen at Hatch 2

Flow Adequate System Operates Adequate Core Core Cooling Damage No Yes 2 No 3 Yes 4f Yes 5 Yes 6 Yes 7 NSIC 149961 - Sequence of Interest for HPCI Fails to Start When the Turbine Stop Valve Fails to Open at Hatch 2 1

RCIC was out of service.

CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS ION NUMBER: 149961

June 11, 1979 ENT: June 3, 1979 LVED: HPCI INVOLVED: water line, valves e improperly closed, leaky water line, (human error)

INTEREST: loss of feedwater flow RRENCE: HPCI fails to start when turbine stop valve fails to open at Hatch 2 E: Hatch 2 ER: 50-366 E: BWR TRICAL RATING: 784 MWe

.9 yr ral Electric NGINEERS: Southern Services/Bechtel Georgia Power Company 11 miles N of Baxley, Ga.

N/A TING CONDITION: hot shutdown URE TYPE OF FAILURE: (a) inadequate performance; (b) failed to start;

_cnýade inoperable; (d) ___________

ETHOD: operational event

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