ENS 43942: Difference between revisions

v t e ENS Event
19:41 Jan 29, 2008
Title	High Pressure Coolant Injection System Not Available for Safe Shutdown Capability
Event Description	The D/C power supply for the Unit 1 High Pressure Coolant Injection (HPCI) system instrumentation has failed resulting in the inability of HPCI to meet its requirement to support safely shutting down the reactor during a Station Blackout (Complete Loss of A/C Power) situation. The Emergency Core Cooling System (ECCS) function of HPCI is still available with the alternate A/C power supply. The licensee is actively troubleshooting the power supply. The HPCI unavailability places the licensee in a 14-day Limiting Condition for Operation action statement. The licensee has notified the NRC Resident Inspector. * * RETRACTION FROM D. SEMETER TO P. SNYDER ON 3/27/08 AT 1300 * * * This is a retraction of the event notification made on 1/29/08 at 21:50 EST hours. This event (#43942) was initially reported as a safety system functional failure under the requirement of 10 CFR 50.72(b)(3)(v)(A). The notification stated that the D.C. power supply for the Unit 1 High Pressure Coolant Injection (HPCI) system instrumentation failed resulting in the inability of HPCI to meet its requirement to support safely shutting down the reactor during a Station Blackout (SBO) (Complete Loss of A/C Power) situation. The Emergency Core Cooling System (ECCS) function of HPCI is still available with the alternate A/C power supply. A review of the station's current licensing basis determined that HPCI is not credited with a safety function during a Station Blackout (SBO) event. Operating procedures direct securing HPCI early in an SBO event to minimize the discharge rate on the Class 1E batteries. The Reactor Core Isolation Cooling (RCIC) system is credited with maintaining reactor inventory during a SBO event. HPCI remained capable of completing its safety function to inject coolant into the reactor pressure vessel during a loss of coolant accident (LOCA) concurrent with loss of offsite power (LOOP) event. The Division 2 automatic initiation logic was inoperable but the Division 4 automatic initiation logic was unaffected by the Division 2 instrument power supply failure. Division 2 instrument power is required for HPCI automatic flow control and would not have been initially available during a LOOP event. However, the Division 2 instrument power would have been restored when the 480 VAC load center is re-energized approximately 13 seconds into the event. The 13 second delay in HPCl injection is offset by existing margin in HPCI's capability to meet the Technical Specification response time of 60 seconds. Therefore, a condition did not exist at the time of discovery that could have prevented the fulfillment of the HPCI safety function. The licensee notified the NRC Resident Inspector. Notified R1DO (Bellamy).

ENS 43942 +/- *RETRACTED*
Where
Limerick Pennsylvania (NRC Region 1)
Reporting

10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor
Time - Person (Reporting Time:+2.15 h0.0896 days <br />0.0128 weeks <br />0.00295 months <br />)
Opened:	Daniel Semeter 21:50 Jan 29, 2008
NRC Officer:	Howie Crouch
Last Updated:	Mar 27, 2008
43942 - NRC Website Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 43942\u003C/a\u003E - \u003Ca href=\"/Limerick\" title=\"Limerick\"\u003ELimerick\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EHigh Pressure Coolant Injection System Not Available for Safe Shutdown Capability\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 43942 - Limerick\n","link":"","lat":40.22646666666667,"lon":-75.58323333333334,"icon":"/w/images/b/be/Constellation_icon.png"}],"imageoverlays":null}
v • d • e

v t e Emergency Notification System
Limerick with 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor
WEEKMONTHYEAR2008-01-29T19:41:00 [Table view]
[ENS list for Limerick]

@@ Line 17: / Line 17: @@
 | event date = 01/29/2008 14:41 EST
 | last update date = 03/27/2008
-| title = High Pressure Coolant Injection System Not Available For Safe Shutdown Capability
+| title = High Pressure Coolant Injection System Not Available for Safe Shutdown Capability
 | event text = The D/C power supply for the Unit 1 High Pressure Coolant Injection (HPCI) system instrumentation has failed resulting in the inability of HPCI to meet its requirement to support safely shutting down the reactor during a Station Blackout (Complete Loss of A/C Power) situation. The Emergency Core Cooling System (ECCS) function of HPCI is still available with the alternate A/C power supply.
 The licensee is actively troubleshooting the power supply.  The HPCI unavailability places the licensee in a 14-day Limiting Condition for Operation action statement.

v t e Unit 1
GE-4
Reactor critical	Critical
Scram	No
Before	Power Operation (98 %)
After	Power Operation (98 %)

ENS 43942: Difference between revisions

Latest revision as of 22:14, 1 March 2018

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ENS 43942: Difference between revisions

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