05000272/LER-2008-001

LER-2008-001, Inadvertent Start of an Emergency Diesel Generator During Testing

Docket Number
Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(iv)(A), System Actuation
2722008001R00 - NRC Website

PLANT AND SYSTEM IDENTIFICATION

Westinghouse — Pressurized Water Reactor (PWR/4) Containment Fan Coil Unit (CFCU) {BK}, Emergency Diesel Generator (EDG) {EK}.

• Energy Industry Identification System {EMS} codes and component function identifier codes, appear as {SS/CCC}

IDENTIFICATION OF OCCURRENCE

Event Date: November 05, 2008 Discovery Date: November 05, 2008

CONDITIONS PRIOR TO OCCURRENCE

Salem Unit 1 was in Operational Mode 5 at 0% reactor power.

No additional structures, systems or components were inoperable at the time that contributed to the event.

DESCRIPTION OF OCCURRENCE

On November 5, 2008, Salem unit 1 was shutdown in Mode 5 completing its nineteenth refueling outage (1R19) activities. During the performance of an overlap test to complete the Technical Specification 4.8.1.1.2 Mode Operation surveillance test for the 11 containment fan coil unit (CFCU) {BK}, the 1A vital bus unexpectedly de-energized and the 1A safeguards equipment controller (SEC) actuated in the blackout mode starting the 1A emergency diesel generator (EDG) {EK}.

-All equipment functioned as designed and control room personnel responded appropriately and in accordance with procedures and policies. Once the operating personnel determined that the actuation was unwarranted, all unnecessary actuated components were stopped, and the 1A vital bus was restored to its normal lineup. The 1A EDG was stopped and placed in its normal standby alignment.

This report is being made in accordance with 10CFR50.73(a)(2)(iv)(A), "any event or condition that resulted in manual or automatic actuation of any of the systems listed in paragraph (a)(2)(iv)(A)...— �NRC FORM 366 (9-2007) PRINTED ON RECYCLED PAPER NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (9-2007) 2. DOCKET1. FACILITY NAME 6. LER NUMBER 3. PAGE 2008 0 0 1000

CAUSE OF OCCURRENCE

The apparent cause of_the event was a technical rigor / human performance error made in the test plan development that was not identified or corrected in the subsequent reviews. The engineer who developed the test plan and the engineer who performed the independent review of the test plan failed to identify that depressing the B1 test button on the 1A SEC would actuate backup trips on the 1A 4KV vital bus infeed breakers, which would de-energize the bus and start the EDG.

PREVIOUS OCCURRENCES

Salem Generating Station LERs for years 2008 back to 2005 were reviewed for similar occurrences of an inadvertent Engineered Safeguard Feature (ESF) actuation during testing. The following two (2) LERs were identified:

The apparent causes and corrective actions associated with these LERs were different and specific to these events and they would have not prevented this occurrence.

SAFETY CONSEQUENCES AND IMPLICATIONS

There were no safety consequences associated with this event. All equipment functioned as designed. Once the operating personnel determined that the actuation was unwarranted, all unnecessary" actuated components were stopped and the plant restored to its normal configuration.

A review of this event determined that a Safety System Functional Failure (SSFF) as defined in NEI 99­ 02, Regulatory Assessment Performance Indicator Guidelines, did not occur. This event did not prevent the ability of a system to fulfill its safety function to either shutdown the reactor, remove residual heat, control the release of radioactive material, or mitigate the consequences of an accident.

CORRECTIVE ACTIONS.

1. An extent of condition review was performed to identify similar test plan errors; no additional errors were identified.

2. The lessons learned were shared with the plant engineering department and station personnel.

3. The Mode Operations surveillance test procedures will be revised to include specific requirements for the use of alternate test methodologies in the event a component(s) is not available for Mode Operations testing or fails to properly actuate during the test. The methodologies will be subject to the same review and approval process rigor as the original surveillance test procedure.

COMMITMENTS

No commitments are made in this LER.