Event Notification Report for August 13, 2001

LOSS OF ONE CONTROL OF THE DOUBLE CONTINGENCY PRINCIPLE

NRC BULLETIN 91-01 24 HOUR NOTIFICATION

At 1415 8/13/01 loose plastic wrap was discovered on a storage shelf in an inadvertent container area and was not configured or secured such that it cannot be deformed into an inadvertent container with an unsafe accumulation potential. This is a violation of control # 5 of NCSA705_076.A03, "Use Of Inadvertent Containers". A pump located on a lower shelf apparently had a pump flange cover dislodged, uncovering a potential inadvertent container. This is a violation of control # 3 of the same NCSA.

The PSS entered an anomalous condition. The plastic wrap and pump were removed from the inadvertent Container area. The PSS exited the anomalous condition.

SAFETY SIGNIFICANCE OF THE EVENTS: LOW

There was no leak of uranium bearing material in the vicinity of the plastic or the uncovered pump.

POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO OF HOW CRITICALITY COULD OCCUR):

For a criticality to occur, the following events would be required: The microfiltration system would have to be processing uranium bearing liquid with an unknown or high concentration of uranium. Then a leak in this system must occur such that an unsafe amount of liquid sprays from the system onto the plastic wrap or uncovered pump. The plastic would then have to deform or the pump would have to fill such that 2.5 liters collects to a depth of greater than 1.5 inches.

CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.): volume, geometry

Inadvertent containers are controlled based upon volume (2.5 liter) or geometry (1.5" or 4" diameter). Flexible material is specifically controlled such that solution cannot pool to a depth greater than 1.5 inches.

ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS):

No uranium material was involved in this event.

NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES

Loose plastic wrap was not configured or secured to prevent deformation into an inadvertent container. The pump flange cover was dislodged. The pump was located on a lower shelf in the same area. This is a violation as control # 5 and # 3 respectively of NCSA-705_076.A.03.


CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEM AND WHEN EACH WAS IMPLEMENTED:

The plastic wrap and pump were removed from the inadvertent container area.



The NRC Resident Inspector was notified of this event report by the certificate holder.

UNEXPECTED REACTOR SCRAM DURING LOGIC SYSTEM TESTING OF EMERGENCY BUS A5.

Pilgrim Unit 1 scrammed from 100% during performance of Logic System Testing of Emergency Bus A5. This is the first time that the Logic System Testing of Emergency Bus A5 had been performed at power. The test is performed once every 24 months and had just been rewritten to be performed at power. The cause of the scram is under investigation at this time but the initiating transient was the loss of Emergency Bus A5. All rods fully inserted into the core. The plant is at 700 lbs. and a controlled depressurization is in progress. Plans are to cool down to less than or equal to 150 lbs. and repair the outboard RCIC steam isolation valve.

Due to deenergization of Emergency Bus A5, Recirculation Pump A tripped and there was a fast transfer of the swing bus (this was expected). The licensee is looking into the transfer of the swing bus causing the trip of Recirculation Pump B. Loss of both operating Recirculation Pumps at power will cause a reactor scram. All systems operated properly. The electrical grid is stable and all Emergency Core Cooling systems are fully operable if needed. The Recirculation pumps will be restarted when the differential temperature between the top and bottom head are within specification.

The NRC Resident Inspector was notified of this event by the licensee.

**** UPDATE ON 08/14/01 AT 1338ET BY V. FALLACARA TAKEN BY MACKINNON ****

This is a supplement report to detail additional information on the scram a Pilgrim, Unit 1 on 08/13/01.

Upon further evaluation of the event and the requirements of 10CFR50.72 and NUREG-1022, Pilgrim is reporting the valid actuation of the following containment isolation groups immediately following the scram: Group 2 (Secondary Isolations), Group 6 (Reactor Water Cleanup), and Reactor Building Isolation with initiation of Standby Gas Treatment Systems. These are expected occurrences in a post-scram transient due to reactor water level shrink below the Reactor Level Setpoint of + 12".

Further plant response issues which are currently under investigation include:

Finalizing the cause of the "B" side RPS actuation.
Determining the cause of the loss of "B" Recirculation Pump.
Resolving a falsely pegged level indication on the "A" Reactor Water Level Indication.
Determining the cause of the loss of 120 VAC bus Y-4.

An event analysis team has been formed to drive out all of these issues.
R1DO (Ron Bellamy) notified.

The NRC Resident Inspector was notified of this event by the licensee.

***** UPDATE FROM VINCENT FALLACARA TO LEIGH TROCINE RECEIVED AT 1420 ON 08/15/01 *****

The following text is a portion of a facsimile received from the licensee:

"This is a supplemental report to further clarify information initially provided concerning logic system testing of the Division 1 Emergency Bus as it related to the 08/13/01 automatic shutdown."

"The initial information indicated that this was the first time this testing had been performed at power and that the test had been rewritten to be performed at power."

"This initial information did not clearly describe the situation concerning this testing. Emergency Bus Relay testing has been successfully performed at power in the past. This test procedure was reformatted to delineate Tech Spec required testing from non-Tech Spec required testing to reduce the unnecessary Diesel Generator unavailability time. During reformatting, an error was introduced which left out a needed prerequisite to successfully complete the Tech Spec required testing of the A-EDG output breaker. This is currently believed to be an initiating event that contributed to the 08/13/01 automatic shutdown."

"At this time, Pilgrim is in Cold Shutdown. The Events Analysis Team continues to investigate previously identified plant issues related to this shutdown."

The licensee plans to notify the NRC resident inspector. The NRC operations officer notified the R1DO (Bellamy).

OFFSITE NOTIFICATION TO THE FLORIDA DEPARTMENT OF ENVIRONMENTAL PROTECTION

An immature green sea turtle was rescued from the plant's intake canal. The turtle is alive but in need of rehabilitation. As required by the plant's sea turtle permit, the Florida Department of Environmental Protection (Florida Fish and Wildlife) was notified of this event.

The NRC Resident Inspector was notified of this event by the licensee.