05000282/LER-2007-002

LER-2007-002,

Docket Number
Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(v), Loss of Safety Function
2822007002R00 - NRC Website

FACILITY NAME (1) � DOCKET NUMBER (2)� LER NUMBER (6) � PAGE (3) 07 -- 02 -- 0

EVENT DESCRIPTION

On June 4, 2007, Nuclear Management Company, LLC (NMC) staff working on the Prairie Island Nuclear Generating Plant (PINGP) transition to National Fire Protection Association (NFPA) standard NFPA-805 discovered non-compliant manual operator actions were credited to achieve safe shutdown in Fire Area 29. Subsequent review for extent of condition identified a number of additional fire areas with non-compliant manual operator actions that were credited for safe shutdown.

EVENT ANALYSIS

NRC Regulatory Information Summary (RIS) 2006-10 provided clarification of the regulatory expectations associated with the use of manual operator actions in 10 CFR 50 Appendix R III.G.1 and III.G.2 fire areas. The non-compliant manual operator actions are considered equivalent to a missing fire barrier, thus, this event is being reported in accordance with 10 CFR 50.73(a)(2)(ii) as an unanalyzed condition.

Impact on Safety System Functional Failure Performance Indicator No actual loss of function occurred as a result of the as-found condition. Consequently, this event is not reportable per 10CFR 50.73(a)(2)(v).

SAFETY SIGNIFICANCE

This event did not result in a loss of function. In the event of a fire in one of the affected fire areas, the manual operator actions that were credited, while not compliant with regulation, would have effectively allowed safe shutdown of the unit. Thus, this event did not affect the health and safety of the public and the safety significance of this event is considered minimal.

CAUSE

The cause of the event is an industry misinterpretation of the regulation. The PINGP Appendix R safe shutdown analysis credited manual operator actions to achieve hot standby, in part, because the regulation did not expressly prohibit manual operator actions. NRC RIS 2006-10 states that operator manual actions for the credited train of equipment may not be credited to achieve hot shutdown.

FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6 PAGE (3) Prairie Island Nuclear Generating Plant Unit 13 05000282 YEAR 07 -- 02 -- 0

CORRECTIVE ACTION

Compensatory measures have been taken in all affected fire areas and this issue is slated to be resolved as part of implementation of NFPA-805. The PINGP Fire Protection Program requires establishment of an hourly fire patrol for an inoperable fire barrier (specifically an inoperable fire barrier penetration) or an alternate compensatory measure that is more effective than an hourly fire patrol. If utilized as a compensatory measure, the noncompliant operator manual actions can provide a more effective compensatory measure than performance of hourly fire patrols. Operator manual actions are allowed to be used as compensatory measures provided the stipulated actions are feasible and reliable. The operator manual actions identified in the procedures for the respective fire areas have been determined to be feasible and reliable. While not acceptable as a compliance strategy for Appendix R, the noncompliant operator manual actions for the respective fire areas are preferable, as an alternate compensatory measure, to the hourly fire patrols that are stipulated by the PINGP Fire Protection Program.

PINGP is transitioning the fire protection license basis to NFPA 805 which will redefine the licensing basis for fire protection thereby precluding recurrence of this event.

PREVIOUS SIMILAR EVENTS

Review of Licensee Event Reports for Unit 1 and Unit 2 since 2004 found no previous similar events related to non-compliant manual operator actions.