| U.S. Nuclear Regulatory Commission
Operations Center Event Reports For
04/21/2006 - 04/24/2006 ** EVENT NUMBERS ** |
 | Fuel Cycle Facility | Event Number: 42165 | 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: KEVIN BEASLEY
HQ OPS Officer: BILL HUFFMAN | Notification Date: 11/22/2005
Notification Time: 15:54 [ET]
Event Date: 11/22/2005
Event Time: 12:05 [CST]
Last Update Date: 04/21/2006 | Emergency Class: NON EMERGENCY
10 CFR Section:
RESPONSE-BULLETIN
| Person (Organization):
KERRY LANDIS (R2)
SCOTT FLANDERS (NMSS)
| Event Text IMPROPER CRITICALITY SPACING FOR WASTE DRUM
"At 1205 CST, on 11-22-05 the Plant Shift Superintendent was notified that during waste drum remediation activities, a drum was discovered that was in violation of one leg of double contingency. Drum #39666W has been determined to contain up to (deleted) g (grams) U235 exceeding the allowed (deleted) gram limit for NCS Spacing Exempt drums. This drum was previously located in an NCS (Nuclear Criticality Safety) Spacing Exempt storage area in violation of NCSA WMO-001 requirements. The drum was moved to the C-335 storage area under an approved Remediation Guide which established a safety basis for the movement of drums that had been roped off and posted per earlier direction. This drum is currently stored in a Temporary Fissile Storage Area maintaining a minimum 2 foot edge-to-edge spacing under NCSA WMO-001, which maintains double contingency."
SAFETY SIGNIFICANCE OF EVENTS
"While the (deleted) gram U235 limit was exceeded for this drum; DAC-832-2A1280-0001 demonstrates that drums containing less than (deleted) grams U235 in an NCS Spacing Exempt array are subcritical. The storage area is roped off and posted to prevent the addition of fissile material to the area; therefore another upset would be required before a criticality is possible."
POTENTIAL CRITICALITY PATHWAYS INVOLVED (BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR)
"This drum is currently stored in the Temporary Fissile Storage Area under NCSA WMO-001, meeting double contingency. In order for a criticality to occur, two independent, unlikely, and concurrent events would have to occur."
CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.)
"Double contingency is maintained by implementing two controls on mass."
ESTIMATED AMOUNT, ENRICHMENT, FORM OF LICENSED MATERIAL (INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS)
"The drum has been determined to contain (deleted) grams U235. Calculations performed demonstrate that drums containing less than (deleted) grams U235 each, in an NCS Spacing Exempt array are subcritical."
NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES
"Although the drum contains greater than the WMO-001 limit of (deleted) grams U235 for NCS Spacing Exempt drums, it has been shown to be less than (deleted) grams U235 based on independent sample results. Calculations performed demonstrate that drums containing less than (deleted) grams U235 each, in an NCS Spacing Exempt array, are subcritical. Therefore, an additional process upset (i.e., spacing upset) would be necessary in order to have a criticality. Therefore, while the drum contained greater than (deleted) grams U235 in the spacing exempt array, the array has been shown to be subcritical for drums containing less than (deleted) grams U235 thus maintaining one leg of double contingency."
CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED
"At the time of discovery, the drum was being stored according to NCS approved spacing controls. The drum will continue to be handled according to approved controls until the U235 mass can be reduced to meet the NCS Spacing Exempt criteria per NCSA WMO-001.
The NRC Senior Resident Inspector has been notified of this event."
See Related Event Report #40700.
* * * UPDATE 1802 EST ON 2/13/06 FROM K. BEASLEY TO S. SANDIN * * *
"At 1100 [CST], on 02-13-06 the Plant Shift Superintendent was notified that two additional waste drums were discovered that exceed the allowed [deleted] gram limit for NCS Spacing Exempt drums and had previously been located in an NCS Spacing Exempt storage area in violation of NCSA WMO-001. The drums are currently stored in a Temporary Fissile Storage Area under NCSA WMO-001, which maintains double contingency.
"The NRC Senior Resident Inspector has been notified of this event."
Notified R2DO(Ayres) and NMSS(Camper).
* * * UPDATE ON 3/20/06 AT 1859 EST FROM B. WALLACE TO HUFFMAN * * *
"At 1430, on 03-20-06, the Plant Shift Superintendent was notified that an additional waste drum has been discovered that exceeds the allowed (deleted) gram limit for NCS Spacing Exempt drums and had previously been located in an NCS Spacing Exempt storage area in violation of NCSA WMO-001. The drums are currently stored in a Temporary Fissile Storage Area under NCSA WMO-001, which maintains double contingency.
"The additional drum was determined to contain (deleted) grams U235. Calculations performed demonstrate that drums containing less than (deleted) grams U235 each, in an NCS Spacing Exempt array are subcritical."
The licensee notified the NRC Resident Inspector. R2DO (Ernstes) and NMSS EO (Pierson) notified.
* * * UPDATE ON 4/20/06 AT 1750 EDT FROM B. WALLACE TO HUFFMAN * * *
" At 1130, on 04-20-06 the Plant Shift Superintendent was notified that an additional waste drum has been discovered that exceeds the allowed (deleted) gram limit for NCS Spacing Exempt drums and had previously been located in an NCS Spacing Exempt storage area in violation of NCSA WMO-001. The drums are currently stored in a Temporary Fissile Storage Area under NCSA WMO-001, which maintains double contingency.
"The additional drum (#41663) was determined to contain (deleted) grams of U235."
The licensee notified the NRC Resident Inspector. R2DO (Lesser) and NMSS EO (Janosko) notified.
* * * UPDATE ON 4/21/06 AT 2040 EDT FROM WALKER TO HUFFMAN * * *
"At 1333, on 4-21-06 the Plant Shift Superintendent was notified that seven additional waste drums had been discovered that exceed the allowed (deleted) gram limit for NCS Spacing Exempt drums and had previously been located in an NCS Spacing Exempt storage area in violation of NCSA WMO-001. The drums are currently stored in a Temporary Fissile Storage Area under NCSA WMO-001, which maintains double contingency.
"Seven additional drums (41160W,41161W,41162W,41158W,41159W,40605W.41681W) were determined to contain in excess of the (deleted) gram limit of U235 but less than the (deleted) gram safety limit."
The licensee notified the NRC Resident Inspector. R2DO (Lesser) and NMSS EO (Janosko) notified. |
| !!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!! | | Power Reactor | Event Number: 42372 | Facility: HATCH
Region: 2 State: GA
Unit: [1] [ ] [ ]
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: FRANK GORLEY
HQ OPS Officer: JOE O'HARA | Notification Date: 02/23/2006
Notification Time: 23:37 [ET]
Event Date: 02/23/2006
Event Time: 18:50 [EST]
Last Update Date: 04/21/2006 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(A) - DEGRADED CONDITION
| Person (Organization):
BRIAN BONSER (R2)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 1 | N | N | 0 | Refueling | 0 | Refueling | Event Text DEGRADED CONDITION OF SHROUD TIE RODS
"While performing Unit One [In-Vessel Visual Inspection] IVVI examination of the four Shroud Tie Rods (Upper Support Horizontal Support Surface) the following results were reported:
"Tie Rod at 135 degree location: Crack-like indications beginning at the inner corner on both sides of the left support and extend to two thirds of the way to the outer corner with full penetration.
"Tie Rod at 225 degree location: Crack-like indication beginning at the inner corner on one side of the left support and extending a small portion of the way toward the outer corner. The indication is similar to that described for the shroud tie rod in the 135 degree location except that it is much less pronounced and is only on one side.
"Tie Rod at 45 degree location: No apparent indications present.
"Tie Rod at 315 degree location: No apparent indications present.
"One of the design criteria of the Shroud Tie Rods is to maintain zero separation between the shroud horizontal welds at 100% uprated power, assuming all of the horizontal welds (H1 thru H8) are fully cracked. The Shroud Tie Rods are also designed to maintain structural integrity of the shroud during all design basis accidents and transients.
"These findings bring into question the ability of these shroud tie rods to have performed their design function with the reactor in operation. This condition constitutes a serious degradation of a principal safety barrier had the unit been operating. The reactor is presently shutdown and the condition discovered does not represent an immediate safety concern for Unit 1. The extent of this condition is believed to be limited to Unit 1, since Unit 2 core shroud tie rods are made of different materials and installed in a different configuration."
The licensee notified the NRC Resident Inspector.
* * * RETRACTION FROM E. BURKETTE TO M. RIPLEY 0859 EDT 04/21/06 * * *
"Retraction of NRC Event # 42372: After further review and evaluation it has been determined that the eight hour call made February 23, 2006 per the guidance of 50.72(b)(3)(ii)(A) should be retracted.
"On 02/23/2006 at approximately 2135 EST, Unit 1 was in the refuel mode. During that time routine inspection of the Reactor Vessel Shroud Restraint Tie Rod Assemblies was in progress. The inspections revealed two cracks on the 135 degree assembly and one crack on the 225 degree assembly. In addition the mechanical preload on the 315 degree assembly was found to be below the design value. These assemblies were originally installed as a mechanical replacement of the horizontal shroud welds.
"An evaluation was performed of the as-found condition that considered the effects of the cracks on the upper supports and the reduced mechanical preload on the 315 degree assembly. The results of the analysis showed that sufficient compression existed for the tie rod assemblies to be considered operable in the as found condition. Inspection and evaluation of the horizontal shroud welds (original plant design) further determined that sufficient intact weld ligament existed to ensure the shroud design function was maintained without relying on the tie rod assemblies. Therefore, the structural integrity of the shroud was and is maintained for normal operation as well as all design basis accidents and transients."
The licensee notified the NRC Resident Inspector. Notified R2 DO (M. Lesser) |
| !!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!! | | Power Reactor | Event Number: 42422 | Facility: HOPE CREEK
Region: 1 State: NJ
Unit: [1] [ ] [ ]
RX Type: [1] GE-4
NRC Notified By: EDWARD CASULLI
HQ OPS Officer: JOE O'HARA | Notification Date: 03/14/2006
Notification Time: 20:21 [ET]
Event Date: 03/14/2006
Event Time: 16:59 [EST]
Last Update Date: 04/22/2006 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
| Person (Organization):
PAUL KROHN (R1)
|
| 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 LOSS OF CONTROL ROOM EMERGENCY FILTRATION
"On 03/14/06 at 1655 hours, the 'A' Control Room Emergency Filtration (CREF) system was removed from service to address a high oil level and subsequent high bearing drain oil temperatures. The 'A' CREF train was declared inoperable and a 7-day LCO was entered. While placing the 'B' CREF train in-service the chiller did not respond as expected. The chiller failed to properly load and supply cooling. At 1659 hours the 'B' CREF train was declared inoperable. This resulted in both 'A' and 'B' trains of CREF [being] unable to perform their design safety function and thus unable to mitigate the consequences of an accident. This failure placed the Hope Creek Station in a Technical Specification 3.0.3 condition requiring a unit shutdown. Oil level was restored to normal band for the 'A' CREF train at 1732 hours and the 3.0.3 condition was exited prior to any actions being initiated to start reducing reactor power to achieve a Hot Shutdown condition.
"A 8 hour report is being made under ECG Section 11.2.2.b, an Event/Condition could have prevented certain safety functions IAW 10.CFR50.72(b)(3)(v).
"At the time of event all safety systems were operable. The license has notified the NRC resident inspector."
* * * UPDATE FROM ZAKARIAN TO HUFFMAN AT 1359 EDT ON 4/22/06 * * *
"This is a retraction of the event notification made on 3/14/06 at 20:21 (ET) hours. This event (#42422) was initially reported as a condition that at the time of discovery could have prevented the fulfillment of a safety function needed to mitigate the consequences of an accident per 10CFR50.72(b)(3)(v)(D). The safety function of the system is to ensure that the ambient air temperature does not exceed the allowable temperature for continuous duty rating for the equipment and instrumentation cooled by this system. Further review has determined that the Control Room Emergency Filtration (CREF) chiller system maintained its capability to complete its specified safety function. During the event, the chilled water and affected room temperatures increased only minimally and remained well below the maximum allowable temperatures. The proceduralized in-progress activity to address the 'A' chiller high oil level condition promptly re-established full system cooling prior to approaching any required temperature limits. The procedure was completed in a timely manner with no complications. Therefore, the temperature limits of the Control Room and equipment rooms would not have been challenged had an event occurred during the time 'A' chiller oil level was being adjusted and the safety function of maintaining room ambient air temperature within limits would have been accomplished."
The licensee has notified the NRC resident inspector. R1DO(Holody) notified. |
| General Information or Other | Event Number: 42513 | Rep Org: NC DIV OF RADIATION PROTECTION
Licensee: SRB TECHNOLOGIES, INC.
Region: 1
City: Winston-Salem State: NC
County:
License #: 0534-1
Agreement: Y
Docket:
NRC Notified By: JAMES ALBRIGHT
HQ OPS Officer: BILL HUFFMAN | Notification Date: 04/19/2006
Notification Time: 18:12 [ET]
Event Date: 04/18/2006
Event Time: [EDT]
Last Update Date: 04/19/2006 | Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
| Person (Organization):
DANIEL HOLODY (R1)
KRISS KENNEDY (R4)
GARY JANOSKO (NMSS)
ILTAB (EMAIL) ()
| Event Text AGREEMENT STATE - LOSS OF 20 TRITIUM FILLED SAFETY MARKERS DURING TRANSPORT
The State of North Carolina reported that 20 "Safety Markers" (Model #SM145), each containing 0.53 Curies of Tritium (Serial #s 803205 through 803224) have been lost by United Parcel Service during transport. The markers were shipped from SRB Technologies, Inc of Winston-Salem, NC, on March 22, 2006, to a customer in Houston, TX. On April 10, SRB was notified by the customer that the shipment was never received. SRB contacted UPS for a trace of the package. On April 18, 2006, UPS notified SRB that the shipment was lost.
The State did not have information on a UPS tracking number or trace number. No information on a point of contact at UPS was available. In addition, there was no information on the last known location of the package.
North Carolina Report #06-14
THIS MATERIAL EVENT CONTAINS A "LESS THAN CAT 3" LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. | |