05000354/LER-2004-001, Regarding Manual Reactor Scram Following Isolation of Primary Containment Instrument Gas (PCIG)

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Regarding Manual Reactor Scram Following Isolation of Primary Containment Instrument Gas (PCIG)
ML040790363
Person / Time
Site: Hope Creek 
Issue date: 03/11/2004
From: Hutton J
Public Service Enterprise Group
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
LR-N04-0095 LER 04-001-00
Download: ML040790363 (7)


LER-2004-001, Regarding Manual Reactor Scram Following Isolation of Primary Containment Instrument Gas (PCIG)
Event date:
Report date:
Reporting criterion: 10 CFR 50.73(a)(2)(iv)(A), System Actuation
3542004001R00 - NRC Website

text

PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 C'

li LR-N04-0095 0 PSEG N\\uclearLLC MAR 1 1 2004 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 LER 354104-001-00 HOPE CREEK GENERATING STATION - UNIT I FACILITY OPERATING LICENSE NO. NPF-57 DOCKET NO. 50-354 This Licensee Event Report entitled 'Manual Reactor Scram following Isolation of Primary Containment Instrument Gas (PCIG)" is being submitted pursuant to the requirements of 10CFR50.73(a)(2)(iv)(A).

Sincerely, James Hutton Plant Manager - Hope Creek Attachment BJT C

Distribution LER File 3.7 I-)/,,-

95-2168 REV. 7/99

Abstract

On January 12, 2004, at 1015 hours0.0117 days <br />0.282 hours <br />0.00168 weeks <br />3.862075e-4 months <br /> during the performance of 18-month Technical Specification calibration of the 'C' channel Reactor Building Exhaust (RBE) radiation monitor, the 'A' channel RBE radiation monitor actuated resulting in an actuation of the Primary Containment Isolation System (PCIS). The actuation of PCIS caused the isolation of the Primary Containment Instrument Gas (PCIG) supply to the inboard Main Steam Isolation Valves (MSIVs). Prior to restoration of the PCIG system, the '0' and 'B' inboard MSIVs began to drift closed. Anticipating the receipt of an automatic scram, the Reactor Operator (RO) manually scrammed the reactor by placing the mode switch to the shutdown position at 1048 hours0.0121 days <br />0.291 hours <br />0.00173 weeks <br />3.98764e-4 months <br />. Shortly after the scram, the 'A' and 'C' MSIVs began to drift closed. At 1051, PCIG was restored and the inboard MSIVs returned to the open position. The inboard MSIVs never went fully closed which ensured that the main condenser remained available throughout the event for reactor heat removal. Following the manual scram, a low reactor water level scram signal was received (Level 3, +12.5 inches) as expected. At 2123 hours0.0246 days <br />0.59 hours <br />0.00351 weeks <br />8.078015e-4 months <br />, a second invalid actuation of the PCIS occurred due to equipment related problems.

The cause of the PCIS actuation that led to the manual scram is attributed to a loose LEMO connector on the 'A' channel RBE radiation monitor that allowed intermittent contact when a nearby conduit was used as a hand hold to gain access to the 'C' channel RBE radiation monitor for surveillance testing. The apparent cause of the second invalid PCIS actuation is attributed to faulty Bailey cards associated with the RBE high radiation input to PCIS. The corrective actions associated with this event consist of procedure enhancements, emphasizing standards with maintenance personnel, re-evaluation of the scheduling of surveillance testing, and the repair/replacement of equipment.

This event is being reported in accordance with IOCFR50.73(a)(2)(iv)(A).

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CORRECTIVE ACTIONS (cont'd):

6. The scheduling of the RBE radiation monitor 18-month surveillance testing will be re-evaluated to assess the risk (development of additional barriers to prevent PCIS actuation) to determine if the surveillance testing should continue to be performed in Operation Conditions 1, 2 or 3 or if the surveillance testing should be performed when the PCIS is not required.

This assessment will be completed by July 30, 2004.

7. A method to more efficiently restore the Primary Containment Instrument Gas (PCIG) system from an invalid isolation will be developed by December 29, 2004. Necessary procedural guidance to implement this method will be issued by February 17, 2005.
8. Bailey logic modules 9-9-2 and 9-9-3, along with optical isolators Al05-Al and A105-A4, associated with the Reactor Building Exhaust high radiation input into PCIS, were replaced.

The actions specified above are being tracked in accordance with PSEG Nuclear's Corrective Action Program.

COMMITMENTS

The corrective actions cited in this LER are voluntary enhancements and do not constitute

commitments