ML20168A731

Final ASP Analysis - St. Lucie 1 (LER 335-77-026)

ML20168A731
Person / Time
Site:	Saint Lucie
Issue date:	06/16/2020
From:	Christopher Hunter NRC/RES/DRA/PRB
To:
Littlejohn J (301) 415-0428
References
LER 1977-026-00
Download: ML20168A731 (4)

Text

y 16, 1977 Offsite Power Lost at St. Luicie 1 re sequence was:

een minutes after a manual reactor trip due to grid disturbances, a em undervoltage condition occurred which caused the reactor coolant s to trip.

diesel-generators started and loaded.

reactor was cooled down using natural circulation until off-site power restored (approximately 20 minutes).

hour later, off-site power was again lost and natural circulation cool-was used until off-site power was restored (one to one-and-a-half s later).

e action; rpose of failed system or component:

site power provides the preferred source of electric power to safety-ted equipment when the unit generator is not in operation.

ility of system per WASH .140G:* loss of offsite power: 2 x 10-5 /hr ility of component per WASH 1400:*

availabilitie are in units of per demand D-1 . Failure rates are in per hour HR-

No No Yes No C 125563 -. Actual Occurrence for Off-Site Power Lost at St. Lucie 1 ecific pumps providing AFW flow not specified.

No 2

3 4

5 6

7 8

9 10' 11 12 13 5563 - Sequence of Interest for Off-Site Power Lost at St. Lucie 1 cluded in mitigation procedures.

ON NU~MBER: 125563 June 16, 1977 T: May 16, 1977 ED: off-site power OLVED: unknown own INTEREST: loss of offsite power ENCE: reactor trip with loss of off site power

St. Lucie 1 R: 50-335

pWR RICAL RATING: 802 MWe 1.1 yr mbustion Engineering GINEERS: Ebasco Florida Power & Light Co.

12 muilea. SEA,f .J.ort. 1ierce, Fla.

/A ING CONDITION: tripped prior to loss of off-site power RE TYPE OF FAILURE: (a) inadequate performance; (b) failed to start; 0 made inoperable; (d) _________

THOD: during operation ER does not specify which AFW system components were used to provide ore cooling.