United States Nuclear Regulatory Commission - Protecting People and the Environment

Morning Report for February 8, 2000

                       Headquarters Daily Report

                         FEBRUARY 08, 2000

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                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

HEADQUARTERS                           X
REGION I                               X
REGION II                              X
REGION III                             X
REGION IV           X
PRIORITY ATTENTION REQUIRED  MORNING REPORT - REGION IV  FEB. 08, 2000

Licensee/Facility:                     Notification:

Entergy Operations, Inc.               MR Number: 4-00-0008
Arkansas Nuclear 1                     Date: 02/08/00
Russelville,Arkansas                   By telephone from SRI
Dockets: 50-313
PWR/B&W-L-LP

Subject: BOTH TRAINS OF LOW PRESSURE INJECTION/DECAY HEAT REMOVAL SYSTEM
         INOPERABLE

Reportable Event Number: 36664

Discussion:

On February 5, 2000, at 12:10 a.m. (CST), the licensee completed a
planned shutdown of Arkansas Nuclear One - Unit 1 to replace a failed
antirotation device on Reactor Coolant Pump D.  During the course of a
normal plant cooldown of the reactor coolant system, operators started
Low Pressure Injection Pump/Decay Heat Removal (LPI/DHR) Pump P-34A at
11:38 a.m. on February 5 to place the decay heat removal system in
service.  After the pump was started, operators received a high
temperature alarm on the pump's inboard bearing, stopped the pump, and
declared it inoperable.  The redundant LPI/DHR Pump P-34B was started and
pump inboard bearing temperature increased and exceeded its alarm
setpoint.  Operators secured Pump P-34B and declared it inoperable at
1:06 p.m. on February 5.  Decay heat removal was never interrupted and
operators continued using reactor coolant pump operation and secondary
system heat removal via a once-through steam generator to the condenser.

During review of the event, the licensee determined that the bearing
lubricating oil for both LPI/DHR pumps had been changed during the last
refueling outage in September 1999.  The oil had been changed to one with
a higher viscosity in an effort to improve pump bearing wear
characteristics. Suspecting that the change in lubricant may have
contributed to the high bearing temperature condition, the licensee
replaced the oil in Pump P-34A with the lower viscosity lubricant that
was used prior to September 1999.  Operators placed the pump in service
for shutdown cooling on February 6 for approximately 1 hour and 10
minutes and observed that bearing temperatures stabilized at normal
levels. The licensee then declared Pump P-34A operable for its decay heat
removal function. Decay heat removal continued with the operating reactor
coolant pumps and steam generator.

On February 6, the licensee also drained the oil from Pump P-34B.
Particulate was observed in the oil and a boroscopic inspection was
performed of the bearings.  Based on oil analysis and the bearing
inspection, the licensee concluded that there was no bearing damage.  The
bearing housings were flushed and refilled with the lower viscosity
lubricant that was used prior to September 1999.  Operators attempted to
test the pump in the shutdown cooling mode on February 7, but had to stop
it when the inboard bearing temperature again approached the alarm
setpoint.

On February 8 at 12:53 a.m., operators placed Pump P-34A in service and
initiated a plant cooldown.  The pump performed normally and operators
stopped the operating reactor coolant pumps at 2:32 a.m. At 5:20 a.m.,
the reactor coolant system temperature was being maintained between 180

REGION IV  MORNING REPORT     PAGE  2          FEB. 08, 2000
MR Number: 4-00-0008 (cont.)

and 190 degrees and reactor coolant system pressure was being maintained
between 225 and 245 psig.  The licensee is maintaining the reactor
coolant system loops operable while repairs are made to Pump P-34B.

Regional Action:

The Region initiated a special inspection on February 8, 2000, to
evaluate the cause of the event and assess the licensee's response to the
event.

Contact:  Phil Harrell               (817)860-8250
          Russ Bywater               (501)968-3290
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