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Event Notification Report for May 5, 2009

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
05/04/2009 - 05/05/2009

** EVENT NUMBERS **


45042 45043

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Fuel Cycle Facility Event Number: 45042
Facility: PADUCAH GASEOUS DIFFUSION PLANT
RX Type: URANIUM ENRICHMENT FACILITY
Comments: 2 DEMOCRACY CENTER
                   6903 ROCKLEDGE DRIVE
                   BETHESDA, MD 20817 (301)564-3200
Region: 2
City: PADUCAH State: KY
County: McCRACKEN
License #: GDP-1
Agreement: Y
Docket: 0707001
NRC Notified By: BILL WALLACE
HQ OPS Officer: BILL HUFFMAN
Notification Date: 05/04/2009
Notification Time: 16:29 [ET]
Event Date: 05/04/2009
Event Time: 05:07 [CDT]
Last Update Date: 05/04/2009
Emergency Class: NON EMERGENCY
10 CFR Section:
RESPONSE-BULLETIN
Person (Organization):
MIKE ERNSTES (R2DO)
GORDON BJORKMAN (NMSS)

Event Text

24 HOUR 91-01 BULLETIN REPORT ON LOSS OF ONE OF TWO CRITICALITY CONTROL CONTINGENCIES


"At 0507 CDT, on 05/04/09 the Plant Shift Superintendent was notified that a fissile sample buggy in C-331 Process Building was in violation of the 2-foot spacing requirement from a fissile HEPA vacuum. The buggy was pushed up against the HEPA vacuum spacing pan which resulted in approximately 21-inches of separation between the fissile material items. The situation has been remediated according to Nuclear Criticality Safety guidelines.

"Since one leg of double contingency was lost, this is being reported to the NRC as a 24-hour Event Report in accordance with NRC BL 91-01 Supplement 1.

"SAFETY SIGNIFICANCE OF EVENTS:
There were approximately 21-inches of separation between fissile material items, therefore, although the minimum 24-inch (2-feet) spacing was violated, there was significant spacing provided.

"POTENTIAL CRITICALITY PATHWAYS INVOLVED:
Even if the items had been configured with no spacing, an additional upset would be necessary in order for a criticality to be possible.

"CONTROLLED PARAMETERS:
Geometry, interaction.

"ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL:
The assay of any material is less than or equal to 5.5 wt. % U235.

"NUCLEAR CRITICALITY SAFETY CONTROL AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES:
The first leg of double contingency relies on maintaining a minimum of 2 feet edge to edge between the HEPA vacuum and other fissile material; this control was violated. The second leg of double contingency, which was not violated, relies on the geometry of the HEPA vacuum cleaner and demonstrates that a single spacing violation is subcritical.

"CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:
Control access to the area. Move the sample buggy in a direction away from the HEPA vacuum such that the spacing is always increasing until the minimum 2-feet edge to edge spacing has been re-established. Double contingency was re-established by 1300 hours on 5/4/09.

"The NRC Senior Resident Inspector has been notified of this event."

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Power Reactor Event Number: 45043
Facility: TURKEY POINT
Region: 2 State: FL
Unit: [3] [ ] [ ]
RX Type: [3] W-3-LP,[4] W-3-LP
NRC Notified By: ED TREMBLAY
HQ OPS Officer: JOE O'HARA
Notification Date: 05/05/2009
Notification Time: 05:41 [ET]
Event Date: 05/05/2009
Event Time: 03:30 [EDT]
Last Update Date: 05/05/2009
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(i) - PLANT S/D REQD BY TS
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
MIKE ERNSTES (R2DO)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
3 N Y 2 Startup 0 Hot Standby

Event Text

3C MAIN STEAM ISOLATION VALVE PROBLEMS

"While preparing to perform main turbine testing prior to returning Unit 3 to service a possible weld defect was identified by plant personnel during a main steam system walk down. This defect appears to be on a small bore section of pipe upstream of a steam trap on a socket weld. This resulted in a small steam leak on the upstream side of the "C" main steam isolation valve. The repair must be completed with the steam line depressurized and as such the plant is in the process of reducing temperature to less than 200 degrees F. Based on previous interpretations of TS 3.4.10 and the applicability to ASME Class 2 piping, TS 3.0.3 has been entered based on current plant conditions.

"At 0348 on 5/5/09, while bringing the Unit 3 to Mode 3 to comply with TSAS 3.0.3, the 3C MSIV failed to close when demanded. The 3C MSIV was declared inoperable and Unit 3 entered TSAS 3.7.1.5 due to the inability to fulfill its safety function. The unit is required to be in Mode 3 in 6 hours and Mode 4 within the following 6 hours.

"At 0437, the 3C MSIV was closed. This is in compliance with TSAS 3.7.1.5. An investigation is in progress as to the cause of the failure of the 3C MSIV to close when demanded.

"Plant shutdown continues to comply with TSAS 3.0.3."

All other safety systems are operable and there is no impact on Unit 4.

The licensee notified the NRC Resident Inspector.

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Thursday, March 29, 2012