05000395/LER-2007-002

LER-2007-002, Failure to Follow Administrative Controls Results in LCO 3.6.4 Violation

Docket Number
Event date:	10-05-2007
Report date:	03-06-2008
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
Initial Reporting
3952007002R01 - NRC Website

PLANT IDENTIFICATION

Westinghouse - Pressurized Water Reactor

EQUIPMENT IDENTIFICATION

XRP0231� Reactor Building Penetration

IDENTIFICATION OF EVENT

On October 5, 2007, while troubleshooting on IFS1900A, RBCU drain flow switch, the administrative controls for establishing demineralized water to the Reactor Building while in Mode 1 were not implemented as required by the Limiting Condition for Operation (LCO) 3.6.4. Therefore, when both the inner and outer containment isolation valves were open between 1027 and 1342 hours0.0155 days <br />0.373 hours <br />0.00222 weeks <br />5.10631e-4 months <br />, the administrative controls were not met.

Condition Report CR-07-02894 was initiated to address this event.

EVENT DATE

10/05/2007

REPORT DATE

12/04/2007 03/06/08

CONDITIONS PRIOR TO EVENT

Mode 1, 100% Power

DESCRIPTION OF EVENT

Troubleshooting on IFS1900A, Reactor Building Cooling Unit drain flow switch was to be performed on October 5, 2007. As part of the troubleshooting plan, demineralized water was to be established to the Reactor Building. A thorough plan was developed to ensure the containment isolation valves were opened under administrative control and to ensure the containment penetration was returned to operable status after the valves were closed.

On the date of the event, the original plan was not strictly followed. Due to stay time considerations, a specific operator was not assigned to the containment isolation valve inside the Reactor Building, although personnel were inside the Reactor Building and had identified the valve location. Since the penetration was declared inoperable, the operating crew erroneously assumed that the administrative controls did not have to be maintained. The administrative controls on the containment isolation valve outside the Reactor Building were relaxed by transferring containment isolation responsibilities to a non-dedicated operator. This resulted in both containment isolation valves being open without administrative controls in place. This violated LCO 3.6.4.

CAUSE OF EVENT

The root cause has been determined to be establishing demineralized water to the reactor building without a formal procedure.

Although confusion existed on the application of VCSNS Technical Specification 3.6.4, the preplanned administrative controls were not formalized in an approved document, so the operating crew was allowed to deviate from the plan without a comprehensive review.

The demineralized water penetration is normally kept drained to prevent overpressurization when it is isolated. The operators confused the fact that the penetration would be declared inoperable when it was not in its drained condition, with the fact that the original plan included administrative requirements to maintain the penetration isolation valves operable when the valves were open. Once this confusion occurred, operators thought that the administrative requirements to allow opening the valves were no longer needed and that the only action required was to isolate the penetration within four hours as required by LCO 3.6.4.c. LCO 3.6.4 describes actions to perform if a containment isolation valve is inoperable, not an entire penetration. In this case, LCO 3.6.4.c did not apply. Since the preplanned administrative controls were not formalized in an approved document, the operators deviated from the preplan without a comprehensive review. They displayed "group-think" in that they believed once the "penetration" was inoperable, there was no need for administrative controls. They relaxed these controls and believed that LCO 3.6.4.c would compensate, but did not realize that the first section of the actions require at least one penetration isolation valve to be operable, which they did not have in this case.

ANALYSIS OF EVENT

Although administrative controls of the containment isolation valves was not continuously maintained, the risk incurred from this evolution was not significant. A Probabilistic Risk Assessment evaluation determined that penetration XRP0231 does not constitute a Large Early Release Frequency (LERF) pathway based on NEI 00-04 section 6.2 and Regulatory Guide 1.201. This penetration satisfies the NEI 00-04 section 6.2 criterion for low safety significance based on a size of less than two inches. This penetration is not considered a potentially significant source of leakage. Two inches is also the established LERF criterion for containment penetration size in the VCSNS PRA. Based on this, there is no change in LERF associated with XRP0231 valves. In addition, in the event of an accident, operators were available to isolate the penetration flowpath in a short period of time.

CORRECTIVE ACTIONS

Immediate corrective action was to drain XRP0231 and return the penetration to operable status. In addition, a procedure will be developed for establishing demineralized water to the reactor building in Modes 1 through 4. Also, due to the similarity between the demineralized water and service air penetrations, a procedure will be developed for establishing service air to the reactor building in Modes 1 through 4.

PRIOR OCCURRENCES

There have been no recent occurrences of inadequate administrative control leading to Technical Specification violations.