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Event Notification Report for December 16, 2008

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
12/15/2008 - 12/16/2008

** EVENT NUMBERS **


44711 44712 44721 44723

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Fuel Cycle Facility Event Number: 44711
Facility: BWX TECHNOLOGIES, INC.
RX Type: URANIUM FUEL FABRICATION
Comments: HEU FABRICATION & SCRAP
Region: 2
City: LYNCHBURG State: VA
County: CAMPBELL
License #: SNM-42
Agreement: N
Docket: 070-27
NRC Notified By: BARRY COLE
HQ OPS Officer: DONALD NORWOOD
Notification Date: 12/10/2008
Notification Time: 15:57 [ET]
Event Date: 12/09/2008
Event Time: 16:30 [EST]
Last Update Date: 12/11/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
PART 70 APP A (b)(2) - LOSS OR DEGRADED SAFETY ITEMS
Person (Organization):
MIKE ERNSTES (R2)
PETER HABIGHORST (NMSS)
FUELS GROUP (OUO) (E-MA)

Event Text

AS-BUILT DEPTH OF LOW LEVEL DISSOLVER SYSTEM DISSOLVER TRAYS EXCEEDED MAXIMUM DESIGN DEPTH

"Event Description: Planned upgrades to the Low Level Dissolver System in the BWXT's Uranium Recovery Facility were undergoing a safety review as part of the change management process. One of the upgrades involved replacement of the dissolver trays to utilize trays of the same length, width, and depth throughout the dissolution process. During the evaluation process a Recovery process engineer questioned differences between the tray heights in the current safety basis and the change review documentation. The ISA summary listed the tray geometry as an Item Relied on For Safety (IROFS). This limit was the same as that discussed in the text of the change management documentation.

"Once it was determined that the discrepancy in the documentation also represented an as-built condition in the field, the Low Level Dissolution process was immediately shutdown pending further evaluation of the safety concern. The IROFS tray geometry was degraded.

"Evaluation of the Event: A review of related safety release documentation indicated the original trays installed in 1999 met the NCS requirements. The requirements limited the tray or allowed modification of the tray (drilling holes, cutting slots) to limit the solution height. Due to the corrosive nature of the process, the trays degrade over time and are replaced when a minimum wall thickness is achieved. The replacement trays were intended to be of like kind. The current fabrication drawing attached to the change management documentation shows no additional features to limit the solution height.

"The initial review of the accident scenario for a geometry upset indicated that although an IROFS was degraded, other IROFS (operator control of mass, operator control of moderator, and poisoning by the tray materials of construction) remained available to assure double contingency. This is a qualitative evaluation that does not analyze the magnitude of the upset condition. The original NCS analysis of the Low Level Dissolver trays conducted in 1999 evaluated tray height; the impact of a range of tray heights was not considered.

"The as-found condition in the field, including tray height, was subsequently modeled using BWXT's validated NCS codes and approved methodology. The normal operating condition was determined to be within the k-effective limit of 0.92 in BWXT's NRC License SNM-42 for a high enriched uranium (HEU) system. When a fully flooded moderation upset condition was analyzed, although the resulting k-effective was shown to
be subcritical, it exceeded the safety limit of 0.95 in BWXT's license for a HEU system. This determination was reached at 4:30 pm on December 9, 2008.

"There was no immediate risk of a criticality or threat to the safety of workers or the public as a result of this event. A fully flooded condition in the Low Level Dissolver is extremely unlikely. The equipment is located on a mezzanine, well above the main process area.

"There are no water sources (e.g., sprinklers) in the area, and the dissolvers are not contained in water tight enclosures. However, with the degradation of the IROFS of tray height, and demonstration that the as-found condition exceeded the license limit for a single upset condition, double contingency could no longer be assured.

"Notification Requirements: BWXT is making this 24 hour report in accordance with 10 CFR 70, Appendix A, (b)(2) loss or degradation of items relied on for safety that results in failure to meet the performance requirement of 70.61.

"Status of Corrective Actions: An investigation of the root causes of this event is ongoing. Corrective actions will be determined as a result of the investigation."

The Low Level Dissolution process remains shutdown.

The licensee documented this event in their condition report CR#1027010.

The licensee notified the NRC Resident Inspector.

* * * UPDATE FROM BARRY COLE TO KARL DIEDERICH ON 12/11/2008 AT 1013 EST * * *

The analysis of a fully flooded moderation upset condition that showed the resulting k-effective exceeded the safety limit of 0.95 in BWXT's license for a HEU system showed a k-effective of 0.96.

Notified R2DO (Ernstes), NMSS (Habighorst), and Fuels Group (via e-mail).

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General Information or Other Event Number: 44712
Rep Org: OHIO BUREAU OF RADIATION PROTECTION
Licensee: COMMUNITY REGIONAL MEDICAL CENTER
Region: 3
City: LORAIN State: OH
County:
License #: 02120480002
Agreement: Y
Docket:
NRC Notified By: MARK LIGHT
HQ OPS Officer: JOE O'HARA
Notification Date: 12/11/2008
Notification Time: 08:34 [ET]
Event Date: 12/10/2008
Event Time: 14:00 [EST]
Last Update Date: 12/11/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
Person (Organization):
CHRISTINE LIPA (R3)
TERRY REIS (FSME)

Event Text

DETECTABLE CESIUM CONTAMINATION FOUND IN SOURCE SAFE DRAWER

A contractor removed cesium sources from a source safe located in a storage area. The sources were removed, packaged, shipped without incident. Surveys were conducted in the safe, and the survey in the lower safe drawer revealed contamination levels greater than 5000 dpm per 100 square centimeters. The lower drawer of the safe has not been used during this recent storage and transfer of sources. The licensee reported to the state that they believed it was "legacy" contamination. Individuals involved in the source transfer were surveyed. No contamination was found. The storage area and passageway to and from the storage area were surveyed. No contamination was found. The licensee has secured the safe and the contaminated area. The area is secured and posted with "no access" signs. The state will follow up with their licensee once a decontamination service completes the decontamination of the affected areas and is ready to release the area for general use.

The state notified Region 3 (Jim Lynch).

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Power Reactor Event Number: 44721
Facility: WATTS BAR
Region: 2 State: TN
Unit: [1] [ ] [ ]
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: KEVIN CASEY
HQ OPS Officer: HOWIE CROUCH
Notification Date: 12/15/2008
Notification Time: 15:40 [ET]
Event Date: 12/15/2008
Event Time: 13:33 [EST]
Last Update Date: 12/15/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
26.719 - FITNESS FOR DUTY
Person (Organization):
MIKE ERNSTES (R2)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation

Event Text

FITNESS FOR DUTY REPORT

A non-licensed employee supervisor had a confirmed positive for illegal drugs during a random fitness-for-duty test. The employee's access to the plant has been terminated. Contact the Headquarters Operations Officer for additional details.

The licensee has notified the NRC Resident Inspector.

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Power Reactor Event Number: 44723
Facility: MONTICELLO
Region: 3 State: MN
Unit: [1] [ ] [ ]
RX Type: [1] GE-3
NRC Notified By: WILLIAM STANG
HQ OPS Officer: JASON KOZAL
Notification Date: 12/15/2008
Notification Time: 22:47 [ET]
Event Date: 12/15/2008
Event Time: 16:16 [CST]
Last Update Date: 12/15/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
Person (Organization):
RICHARD SKOKOWSKI (R3)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation

Event Text

UNANALYZED CONDITION DUE TO STEAM CHASE TEMPERATURE GREATER THAN 165F

"At 1616 on 12/15/08, a plant heating boiler trip resulted in a loss of a reactor building ventilation. The loss of reactor building ventilation resulted in maximum average main steam chase temperatures greater than or equal to 165F. High energy line break (HELB) analysis of piping in the steam chase assumes an initial average temperature prior to the break of 165F. Temperature greater than or equal to 165F in the steam chase challenges EQ qualification of the piping analysis. Abnormal procedures for loss heating boiler and ventilation system failure were entered. C.3 (Shutdown) and C.5-1300 (secondary containment control) were also entered. The plant heating boiler was restarted and ventilation restored prior to power reduction. All systems have been returned to normal."

The licensee notified the NRC Resident Inspector.

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Thursday, March 29, 2012