05000272/LER-2001-005

LER-2001-005,

Docket Number
Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
2722001005R00 - NRC Website

FACILITY NAME (1) DOCKET (2)

PLANT AND SYSTEM IDENTIFICATION

Westinghouse — Pressurized Water Reactor Control Room Emergency Air Conditioning System (CREACS) {VI} 125 VDC system (batteries, battery chargers, busses, etc.) {EJ} * Energy Industry Identification System {EIIS} codes and component function identifier codes appear as (SS/CCC)

CONDITIONS PRIOR TO OCCURRENCE

Salem Unit 1 was in Mode 6, refueling, at the time of the event.

Salem Unit 2 was in Mode 1, power operation at the time of the event.

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

DESCRIPTION OF OCCURRENCE

On April 18, 2001 at 1400, and then again at 1409, fuel movement occurred in the Spent Fuel Pool while the Unit1 Control Room Emergency Air Conditioning System (CREACS) was available, but not OPERABLE.

Technical Specification 3.7.6.1 action f (modes 5 and 6), requires the CREACS be OPERABLE in all modes during core alterations and movement of irradiated fuel assemblies. The CREACS Intake Dampers for Unit 1 are powered from the 1B and 1C 125 VDC busses. The Unit 1 CREACS was available with the DC bus powered by the battery charger. However, it was not OPERABLE due to the 1B 125 VDC battery disconnect (EJ/DISC) being open to support maintenance on the 1B battery (EJ/BTRY). With the 1B battery disconnect open, emergency intake dampers, although available to support Unit 2 (dampers would have remained closed), were not Technical Specification OPERABLE to support fuel movement at Unit 1.

ANALYSIS OF OCCURRENCE

The intake dampers on the outside emergency air-conditioning duct are powered from the 1B and 1C 125 VDC busses. With the 1B battery disconnect open, the intake dampers should have been declared inoperable and actions initiated to place at least one isolation damper in the closed position, prior to allowing fuel movement in the Spent Fuel Building. The required Technical Specification was not entered; therefore compensatory actions required by Technical Specifications were not performed.

The CREACS was inoperable due to the 1B battery disconnect being open. The CREACS would have functioned to place the Control Room in the Accident Pressurized Mode. As a result, this event did not pose any nuclear or radiological safety impact.

FACILITY NAME (1) DOCKET (2)

ER

ANALYSIS OF OCCURRENCE (continued) Operation of the disconnect switches allows maintenance to be performed on the respective battery, while maintaining the 125 VDC bus energized via the 125 VDC battery charger (EJ/BYC).

Procedure changes to the respective 125 VDC Bus Operation procedures were incorporated to direct operation of the battery disconnect switches, however, additional procedure changes are required to provide the necessary guidance to preclude recurrence of events similar to this event.

CAUSE OF OCCURRENCE

This condition was caused by weakness in the understanding, by all individuals' involved (licensed operators, outage control center), of all requirements for operability versus availability of the Control Area Ventilation (CAV) system. This was compounded by the recent installation of battery disconnect switches and accompanying procedure changes. While Precaution and Limitation 3.4 of S1(2).0P-10.ZZ-0010(Q), Spent Fuel Pool Manipulations, indicates control room emergency air conditioning system (CREACS) shall be operable-as defined by TS 3.7.6.1action f (modes 5 and 6), the recent addition of 125 VDC battery disconnect switches warrants additional procedure changes to provide clarification on operability requirements. These changes will be incorporated in to the appropriate Operations and Maintenance procedures. A root cause analysis was performed which was associated with defense in depth for station power. This analysis provides additional Corrective Actions that would have assisted to preclude the occurrence of a similar event.

PRIOR SIMILAR OCCURRENCES

A review of LERs from 1998 through the present for both Salem and Hope Creek identified no similar occurrences.

SAFETY CONSEQUENCES AND IMPLICATIONS

There were no safety consequences or implications associated with this event. The dampers were closed and would remain closed on loss of power from the battery. Although inoperable, should a fuel handling control room in the accident pressurized mode. Similarly, if Unit 2 had a loss of coolant accident coincident with loss of offsite power, these dampers would have opened since power was available from the battery charger.

A review of this event determined that a Safety System Functional Failure (SSFF) as defined in NEI 99-02 did not occur.

FACILITY NAME (1) DOCKET (2)

CORRECTIVE ACTIONS

1. Appropriate Operations and Maintenance procedures will be revised to provide additional guidance regarding operation of the battery disconnect switches with regard to CAV operability/availability.

2. The Training Review Group will evaluate the need for additional training of Operations Department personnel on CAV availability versus operability.

COMMITMENTS

The corrective actions cited in this LER are voluntary enhancements and do not constitute commitments.