05000219/LER-2004-007
| Docket Number11 22 2004 20042- 007 - 00 01 21 2005 | |
| Event date: | |
|---|---|
| Report date: | |
| 2192004007R00 - NRC Website | |
Description of Event
On November 22, 2004 at 10:41 a.m. during startup operations following 1R20 Refueling Outage, a reactor operator (RO) bypassed the automatic Containment Ventilation and Purge Isolation (EIIS-JM) function due to an incorrect step in the plant start-up procedure. The incorrect step had the wrong nomenclature and directed the RO to a key-locked bypass control switch (CFI-HS) only intended to be used in implementing Emergency Operating Procedure (EOP) actions. The bypass condition was addressed after reviewing the Nitrogen System and Containment Atmosphere Control (CAC) Procedure 312.11 and placing the switch in the correct position, thus clearing the alarm and exiting the condition.
Total elapsed time for the event is as follows:
10:41 a.m. Containment Ventilation and Purge Isolation Bypassed in Alarm.
12:22 a.m. Containment Ventilation and Purge Isolation Switch placed in Normal
Analysis of Event
The procedure error was the insertion of the wrong bypass switch nomenclature (Containment Ventilation and Purge Isolation Bypass vice the correct nomenclature, Drywell Vent and Purge Valves Interlock Bypass). The error was introduced into the procedure in July 2001. Startups since July 2001 had inerting in progress in accordance with procedure 312.11, prior to the Reactor Mode Switch placed in RUN, and as such, the procedure 201 step in error was not applicable. No plant conditions were present (placing the Reactor Mode Switch in RUN prior to containment being inerted) that required the bypassing of the Drywell Vent and Purge Valve Interlock until November 22, 2004.
This event is reportable in accordance with 10CFR50.73 (a)(2)(v), any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to: (C) Control the release of radioactive material". This condition was also, by definition, a Safety System Functional Failure (SSFF) in accordance with NEI 99-02 for PI Data reporting purposes.
Cause of Event:
The apparent cause of this event was an incorrectly worded step in the plant startup procedure 201.
Corrective Actions:
Procedure 201, Plant Startup, will be revised to correct the bypass switch nomenclature.