Hope Creek: Indications Of Big Maintenence Issues (2) At The Plant

Licensee Event Report 2019-001-00

At 1906 EDT on August 3 2019, while in OPCON 1 at 93.8 percent power, operators identified degrading main condenser vacuum and commenced reducing power. Degrading vacuum was due to the circulating water cooling tower bypass valve failing open. At 1947, the reactor was manually scrammed from 37 percent due to loss of condenser vacuum. Reactor feedwater pumps (RFP) tripped when reactor pressure vessel (RPV) water level rose to level 8 (+54 inches) because the reactor feedwater startup level control valve (SULCV) failed open. Operators initiated the reactor core isolation cooling (RCIC) system, recovered a RFP and secured RCIC after establishing control of RPV water level. The failed equipment was replaced.
This event is reportable per 10 CFR 50.73(a)(2)(iv)(A).

IDENTIFICATION OF OCCURRENCE Event Dates: August 03, 2019 Discovery Dates: August 03, 2019
CONDITIONS PRIOR TO OCCURRENCE Hope Creek was in Operational Condition (OPCON) 1 - Power Operation, 37 percent power.

DESCRIPTION OF OCCURRENCE At 1906 EDT on August 3, 2019, while in OPCON 1 at 93.8 percent power, operators identified degrading main condenser vacuum and commenced reducing power. Degrading vacuum was due to the circulating water {KE} cooling tower bypass valve failing open. At 1947, the reactor was manually scrammed from 37 percent due to loss of condenser vacuum. Reactor feedwater {SJ} pumps (RFP) tripped when reactor pressure vessel (RPV) water level rose to level 8 (+54 inches) because the reactor feedwater startup level control valve (SULCV){JB} failed open. Operators initiated the reactor core isolation cooling (RCIC){BN} system, recovered a RFP and secured RCIC after establishing control of RPV water level. The failed equipment was replaced.

 

This event is reportable per 10 CFR 50. 73(a)(2)(iv)(A).

CAUSE OF EVENT A Bailey solid-state logic module failure caused the cooling tower bypass valve to open; which led to loss of main condenser vacuum. A pneumatic relay failure caused the SULCV to fail open.

SAFETY CONSEQUENCES AND IMPLICATIONS There were no safety consequences as a result of this event. The Reactor Protection System {JC} system operated as designed to shut down the reactor. The RCIC system operated as designed to inject water into the reactor core. 

PREVIOUS EVENTS A review of station Licensee Event Reports and the corrective action program for the past three years was performed. No LERs were identified and no issues were documented in the corrective action program for similar conditions.

1. FACILITY NAME 2. DOCKET
Hope Creek Generating Station 05000354
NARRATIVE CORRECTIVE ACTIONS
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3. LERNUMBER YEAR SEQUENTIAL REVISION NUMBER NUMBER 2019 - 001 - 00
The Bailey solid-state logic module for the cooling tower bypass valve was replaced and guidance was issued to tag the cooling tower bypass valve closed to prevent spurious opening when not needed. The SULCV pneumatic relay was replaced.
COMMITMENTS This LER contains no regulatory commitmen