Event Notification Report for May 11, 1999

LEAD SHIELDING INSTALLED ON FUEL POOL COOLING SYSTEM PIPING CAUSES HANGER DESIGN CRITERIA TO BE EXCEEDED.

DURING A REVIEW OF CALCULATIONS FOR PIPE HANGERS AND SUPPORTS ASSOCIATED WITH FUEL POOL COOLING SYSTEM PIPING, IT WAS DETERMINED THAT PIPE SUPPORTS PS-13 AND 14 DO NOT MEET THE DESIGN CRITERIA OF ANSI B31.1 1955. HOWEVER, THEY DO MEET THE OPERABILITY REQUIREMENTS OF NRC GENERIC LETTER 91-18. SINCE THIS SYSTEM IS STILL OPERABLE, NO COMPENSATORY ACTIONS ARE REQUIRED AT THIS TIME. THE CONDITION WAS CAUSED BY A PRIOR INSTALLATION OF LEAD SHIELDING ON THE PIPING. THE LICENSEE'S CORRECTIVE ACTION IS TO EVALUATE THE SUPPORTS FOR MODIFICATIONS OR REMOVE THE ADDED LEAD SHIELDING FROM THE PIPING.

THE RESIDENT INSPECTOR WILL BE INFORMED.

CENTRAL CONTROL ROOM (CCR) TOXIC GAS MONITOR SETPOINTS MAY DRIFT BEYOND TECH SPEC (TS) LIMITS.

DURING AN ENGINEERING EVALUATION OF TOXIC GAS MONITOR SETPOINTS, IT WAS DETERMINED THAT AMMONIA MONITOR DRIFT COULD POSSIBLY CAUSE THE PLANT TO EXCEED THEIR TS ACTUATION LIMIT. CURRENTLY, THEIR SETPOINT FOR AMMONIA ACTUATION IS 21 PPM (TS LIMIT IS 25 PPM), AND THE CALCULATED DRIFT OCCURRING IN ONE QUARTERLY PERIOD WOULD BE 18 PPM. ADDING THE TWO VALUES (21 PPM AND 18 PPM) WOULD RESULT IN THE PLANT EXCEEDING ITS TS LIMITS, PUTTING THE PLANT INTO AN LCO ACTION STATEMENT.

AS REQUIRED BY TS ACTION STATEMENT, THE CCR VENTILATION SYSTEM WAS PLACED IN INTERNAL RECIRCULATION (INCIDENT MODE) AT 1323 TO RESTORE TO DESIGN AND EXIT THE LCO ACTION STATEMENT.

THE RESIDENT INSPECTOR WILL BE NOTIFIED.

WHILE PERFORMING A HEAVY LOAD LIFT OVER AN OPEN FUELED REACTOR VESSEL, THE PLANT WENT OUTSIDE ITS DESIGN BASIS.

ON 05/12/99, THE LICENSEE DETERMINED THAT, DURING AN EVOLUTION ON 05/08/99, THE UPPER INTERNALS (A "HEAVY LOAD") WAS TRANSPORTED OVER THE OPEN UNIT 1 REACTOR, WHICH CONTAINED FUEL, WHILE THE CONTAINMENT IN-SERVICE PURGE WAS OPERATING. THE USAR STATES: "DURING HEAVY LOAD LIFTS OVER THE OPEN FUELED REACTOR VESSEL, AT LEAST ONE ISOLATION VALVE WILL BE CLOSED IN EACH LINE PENETRATING THE CONTAINMENT ATMOSPHERE TO THE OUTSIDE." THE UNIT WAS, THEREFORE, OUTSIDE THE DESIGN BASIS SINCE NO ISOLATION VALVES FOR THE IN-SERVICE PURGE PENETRATIONS WERE CLOSED DURING THIS EVOLUTION. THE HEAVY LOAD MOVEMENT WAS COMPLETED WITHOUT INCIDENT. NOTE THAT THE IN-SERVICE PURGE DISCHARGE IS FILTERED, AND THE AUTOMATIC ISOLATION OF THESE PENETRATIONS, UPON HIGH RADIATION, WAS OPERABLE.

THE RESIDENT INSPECTOR WILL BE NOTIFIED.

BOTH DIESEL GENERATORS DECLARED INOPERABLE

During the review (on 6/10/99 @ 1330) of an event in which the "A" Diesel Generator (D/G) output breaker failed to close during periodic testing, it was discovered that the plant had operated for a period of time with both required D/Gs inoperable. Based on the identified failure mode, the "A" D/G breaker was in an inoperable state since the last time it was tripped. This occurred following the performance of periodic testing on 5/11/99 @ 1148. On 5/11/99 @ 1334, the "B" D/G was declared inoperable for the performance of periodic testing, which resulted in both D/Gs being inoperable and the plant entering a 3.0.3 TS LCO action statement. Therefore, during the periodic testing of the "B" D/G, there would have been an inability to automatically respond to an event coincident with a loss of offsite power. The "B" D/G was immediately returned to service following the test. The "A" D/G was restored to operable status on 6/9/99. The licensee notified the NRC Resident Inspector.

* * * UPDATE AT 1519 ON 6/30/99 BY DOUG PETERSEN TO JOLLIFFE * * *

The licensee has concluded that the date and time of inoperability is when the "A" D/G output breaker to safeguards bus #14 failed to close (1007 on 6/8/99). The "A" D/G was declared operable on 6/9/99, and the time of inoperability is within the allowable LCO time frame. Therefore, no reportable event occurred and the licensee desires to retract this event.

During troubleshooting, the breaker was successfully closed at the bus cubicle more than 20 times on 6/8/99 and 6/9/99 without any adjustment of the breaker and without another failure. The apparent cause of the breaker failure is attributed to a slight misalignment of the tripper bar on the breaker. However, potential effects of bus vibration, temperature, lubrication drying, and the randomness of the breaker failure does not provide firm evidence of the specific time the breaker became inoperable. There is no firm evidence to believe the discrepancy existed prior to 6/8/99. Therefore, in accordance with the industry guidance provided in NUREG-1022, Revision 1, it should be assumed the discrepancy occurred at the time of its discovery. The licensee notified the NRC Resident Inspector.

The NRC Operations Officer notified the R1DO Larry Doerflein.