Event Notification Report for April 28, 1999

HPCI SYSTEM INOPERABLE

During an I&C surveillance test of pressure switches associated with the High Pressure Coolant Injection (HPCI) steam line, one of four low steam line pressure switches failed its test. The licensee closed both HPCI steam isolation valves rendering HPCI inoperable. The licensee has verified the operability of the Automatic Depressurization System as required by plant technical specifications.

The NRC resident inspector has been informed of this notification by the licensee.

*************** UPDATE AT 1106 ON 05/05/99 FROM ANDREW WISNIEWSKI TO TROCINE ***************

The HPCI system was taken out of service (isolated) because of an inoperable pressure switch which was part of the primary containment isolation system (PCIS). After further review, the licensee determined that the system was intentionally removed from service in accordance with the technical specifications for PCIS. Therefore, the licensee believes that this event is not reportable and is retracting this event notification.

The licensee plans to notify the NRC resident inspector, and the licensee's Corporate Office may notify the state. The NRC operations officer notified the R1DO (Linville).

FAILURE OF AN EMERGENCY SYSTEM WITH NO REDUNDANT EQUIPMENT AVAILABLE FOR BACKUP - 24-HOUR REPORT IN ACCORDANCE WITH 10CFR40.60(b)

The failure involves a health physics vacuum pump and a communication device (the red lights for notification of respiratory conditions). Power is not available to these devices. The licensee cannot switch to standby power due to a common bus outage. The licensee was in the process of putting another scrubber onto this system as part of an annual shutdown. The power feed coming in from the local company (CIPS) went down, and the standby system was not available due to ongoing work. The power outage occurred at 1003 CDT, and it lasted for 2 minutes and 10 seconds. The licensee determined that the health physic pump and red lights were inoperable at 1030 CDT.

Prior to this event, the fluorination and distillation portions of this UF6 conversion facility were down, and the licensee was operating the uranium tetra-fluoride (UF4) portion of the facility. The licensee shut this portion of the facility down a few minutes ago because there was no standby power to the area due to a common bus outage.

The licensee plans to inform the NRC Region 3 office and three NRC inspectors that are currently located on site. (Call the NRC operations officer for a licensee contact telephone number.)

DISCOVERY OF A SAFEGUARDS SYSTEM DEGRADATION RELATED TO THE PROTECTED AREA
(1-HOUR REPORT)

Security personnel discovered a safeguard system degradation related to the protected area. Immediate compensatory actions were taken upon discovery. (Contact the NRC operations officer for additional details.)

The licensee notified the NRC resident inspector.

- HPCI SYSTEM INOPERABLE DUE TO TRIPPED BAROMETRIC CONDENSER VACUUM PUMP BREAKER -

AT 1800 ON 04/28/99, WITH UNIT 1 AT 16% POWER, THE HIGH PRESSURE COOLANT INJECTION (HPCI) SYSTEM BAROMETRIC CONDENSER VACUUM PUMP TRIPPED DURING A TECH SPEC SURVEILLANCE TEST. PLANT OPERATORS WERE UNABLE TO RESET THE VACUUM PUMP CIRCUIT BREAKER AND SHUT THE HPCI SYSTEM DOWN AND DECLARED IT INOPERABLE. MAINTENANCE ELECTRICIANS RESET THE VACUUM PUMP CIRCUIT BREAKER THERMAL OVERLOADS RESTORING POWER TO THE VACUUM PUMP. MAINTENANCE ELECTRICIANS REPLACED THE HPCI SYSTEM VACUUM PUMP CONTROL SWITCH BECAUSE THE SWITCH HAS RECENTLY EXPERIENCED PROBLEMS NOT RETURNING TO ITS MID POSITION, AS DESIGNED. THE LICENSEE IS CONTINUING TO INVESTIGATE THE CAUSE OF THE VACUUM PUMP TRIP.

TECH SPEC LCO ACTION STATEMENT 3.5.1 REQUIRES THE LICENSEE TO VERIFY THE OPERABILITY OF THE REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM AND RESTORE THE HPCI SYSTEM TO OPERABLE STATUS WITHIN 14 DAYS OR SHUT UNIT 1 DOWN. AT 1925, THE LICENSEE VERIFIED THE OPERABILITY OF THE RCIC SYSTEM.

THE LICENSEE PLANS TO INFORM THE NRC RESIDENT INSPECTOR.

- Fuel Building inoperable due to loss of vacuum in Fuel Building due to an open Fuel Building/Annulus door -

At 2151 CDT on 04/28/99, with the plant in Operational Condition 5 in a refueling outage, the Fuel Building was determined to be inoperable. At the time, fuel inspection activities were in progress in the Fuel Building.

The Fuel Building was rendered inoperable when a Fuel Building/Annulus door was opened. The door was opened to allow entry of personnel for completion of required testing of lighting circuits. The control room staff was alerted to this condition when the "Fuel Building Pressure High" alarm was received. Upon receipt of the alarm, the Control Room Supervisor directed that fuel handling activities be suspended. Fuel handling activities were immediately suspended and not resumed until the door was closed to reestablish Fuel Building integrity.

The fuel inspection activities in progress consisted of removing single fuel pins from an irradiated bundle. The irradiated bundle was located in the fuel preparation machine.

The Fuel Building/Annulus door was required to be closed to maintain the leak tightness of the Fuel Building. Plant staff personnel are continuing to evaluate this event. However, as a result of the open door, the Fuel Building may not have been able to perform its design function.

The licensee informed the NRC Resident Inspector.

24-HOUR NRC BULLETIN 91-01 REPORT

The following is text from a facsimile submitted to the NRC Operations Center:

"During a walkdown of C-710, room 6, a group of small chemical traps with tags indicating less than 5 pounds of uranium were discovered in violation of [the] NCSA GEN-10 two-foot spacing requirement for UH pieces of equipment. These items were improperly categorized as spacing exempt based on the size criteria of having dimensions in all directions greater than that of a 5.5 gallon drum. Fifty-three items would be required prior to exceeding the UH mass at 2.0 wt. % U235. Similar incidents involving the violation were also discovered in C-710, room 2, C-409, and C-720. GEN-10 states that UH items must be spaced a minimum of two feet edge-to-edge from other UH items to preclude the accumulation of an unsafe uranium mass.

"This event is being categorized as a 24-hour event in accordance with Safety Analysis Report Table 6.9-1, Criterion A4.a, and Bulletin 91-01, Supplement 1.

"SAFETY SIGNIFICANCE OF EVENTS:

"Although the amount of Fissile material present is far below safe mass for each item, double contingency was not maintained because the items were not handled as UH and properly spaced.

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

"In order for a criticality to be possible, greater than 104 of these items which contain less than 5 pounds of uranium each would need to be accumulated.

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

"Interaction and mass

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

"Variable amount. 2.0 wt. % U235, in the form of UO2F2, with a process limit of approximately 600 lbs. at 2.0 wt. % U235

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

"The two process conditions relied on in this scenario for double contingency are mass and interaction.

"The first leg of double contingency is based on limiting the mass of uranium at 2.0 wt. % U235 to 264 pounds of uranium. This is controlled by quantifying the mass of each item using independent NDAs/visual inspections. Each individual item contains less than 5 pounds of uranium: therefore, this control was not violated. The total mass of all the items placed together at each location is less than the UH mass limit.

"The second leg of double contingency is based on limiting interaction between UH items. This is controlled by maintaining minimum two-foot edge-to-edge spacing between UH items. Spacing was not maintained between the items: therefore, this requirement was violated and the process condition was lost,

"Since a control relied upon for double contingency was violated, double contingency was lost."

The NRC resident inspector has been informed of this notification.

* * * * * * * * * * UPDATE AT 1212 EDT ON 05/05/99 FROM TOM WHITE TO FANGIE JONES * * * * * * * * * *

"Plant walkdowns have revealed additional locations which are also inappropriately spaced under GEN-10 criteria. These additional locations are:

C-335, 15 pallets of valve parts, totaling less than 52 items
C-400, 2 centrifugal pump casings

"The amount of fissile material is far below the safe mass for each item and is less than the number of items needed to be greater than a safe mass. NCS incident report NCS-INC-99-024 has been revised to encompass these new locations."

The NRC resident inspector has been notified of this update, and the onsite Department of Energy site representative will be notified by Paducah personnel. The NRC Headquarters Operations Officer notified the R3DO (Monte Phillips), NMSS EO (Don Cool), and IRO (Frank Congel)

**** UPDATE ON 5/6/99 @ 1711 FROM WHITE TO GOULD ****

DURING A PLANT WALKDOWN, AN ADDITIONAL LOCATION WAS REVEALED THAT IS ALSO INAPPROPRIATELY SPACED UNDER GEN-10 CRITERIA. THE LOCATION IS C-720 STORES WHICH HAS FOUR 4" AND TWO 6" G-17 VALVES. THE AMOUNT OF FISSILE MATERIAL IS FAR BELOW THE SAFE MASS FOR EACH ITEM AND IS LESS THAN THE NUMBER OF ITEMS NEEDED TO BE GREATER THAN A SAFE MASS. NCS INCIDENT REPORT NCS-INC-99-024 HAS BEEN REVISED TO ENCOMPASS THE NEW LOCATION.

THE RESIDENT INSPECTOR WILL BE INFORMED.

THE REG 3 RDO(PHILLIPS) AND NMSS EO(GREEVES) WERE NOTIFIED