Event Notification Report for February 03, 2011
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/02/2011 - 02/03/2011
Fuel Cycle Facility
Event Number: 46592
Facility: PADUCAH GASEOUS DIFFUSION PLANT
Region: 2 State: KY
Unit: [] [] []
RX Type: URANIUM ENRICHMENT FACILITY
Comments: 2 DEMOCRACY CENTER
6903 ROCKLEDGE DRIVE
BETHESDA, MD 20817 (301)564-3200
NRC Notified By: CALVIN PITTMAN
HQ OPS Officer: DONG HWA PARK
Region: 2 State: KY
Unit: [] [] []
RX Type: URANIUM ENRICHMENT FACILITY
Comments: 2 DEMOCRACY CENTER
6903 ROCKLEDGE DRIVE
BETHESDA, MD 20817 (301)564-3200
NRC Notified By: CALVIN PITTMAN
HQ OPS Officer: DONG HWA PARK
Notification Date: 02/04/2011
Notification Time: 09:05 [ET]
Event Date: 02/03/2011
Event Time: 09:30 [CST]
Last Update Date: 02/04/2011
Notification Time: 09:05 [ET]
Event Date: 02/03/2011
Event Time: 09:30 [CST]
Last Update Date: 02/04/2011
Emergency Class: NON EMERGENCY
10 CFR Section:
10 CFR Section:
Person (Organization):
GEORGE HOPPER (R2DO)
PATTI SILVA (NMSS)
GEORGE HOPPER (R2DO)
PATTI SILVA (NMSS)
24 HOUR NOTIFICATION UNDER BULLETIN 91-01 CONCERNING LEAKAGE OF MODERATING LIQUID
"At 0930 CST on 02-03-11, the Plant Shift Superintendent (PSS) was notified that a steam condensate line broke above the C-310 withdrawal room and water leaked through the ceiling into the withdrawal room on the ground floor. Water accumulated greater than 0.5 inch in depth in the diked area above the withdrawal room in violation of NCSA [Nuclear Criticality Safety Approval] 310-004. NCSA 310-004 requires that open containers with volumes greater than 5.5 gallons shall not contain pre-existing moderator greater than 0.5 inches in depth. During the walk down, it was discovered that the sprinkler heads currently installed above the withdrawal room are rated at 160F in violation of the NCS [Nuclear Criticality Safety] limit. NCSE [Nuclear Criticality Safety Evaluation] 032 requires the minimum activation temperature to be no lower than 200F. The sprinkler system was taken out of service and drained at 2131 CST on 02-03-11 and the level of water accumulated in the diked area was verified to be less than 0.5 inches at 0426 CST on 02-04-11.
"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.
"The NRC Senior Resident Inspector has been notified of this event.
SAFETY SIGNIFICANCE OF EVENTS
"The first leg of double contingency is based on preventing a release of fissile material greater than the safe mass of uranium. This event did not release fissile material greater than the safe mass of uranium.
POTENTIAL CRITICALITY PATHWAYS (BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR)
"In order for a criticality to be possible, a large UF6 release containing greater than a critical mass of uranium would have to occur and accumulate greater than the critical configuration.
CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.)
"The two process conditions relied upon for double contingency are mass and geometry.
ESTIMATED AMOUNT, ENRICHMENT, FORM OF MATERIAL (INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS)
"Product withdrawal assay at the time of the event was less than 4.95 wt% U235. However, no UF6 release occurred.
NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES
"The first leg of double contingency is based on preventing a release of fissile material greater than the safe mass of uranium. Since a UF6 release containing greater than the safe mass has not occurred, the mass parameter has maintained. The second leg of double contingency limiting moderating liquids in open containers to less than 0.5 inches and requiring the sprinkler head activation temperature to greater than 200F. Since the diked area above the withdrawal room did accumulate water level greater than 0.5 inches, the control was violated. Additionally, since the installed sprinkler heads activation temperature is less than 200F, a design feature of NCSE 032 was violated. Therefore, double contingency was not maintained.
CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED
"Shiftly checks of the diked area above the withdrawal have been initiated to ensure water level is not accumulating. The condensate leak above the withdrawal room was repaired and solution level verified to be less than 0.5 inches (0426 [CST] on 2/4/11). The sprinkler systems associated with the sprinkler heads above the withdrawal room have been isolated until the sprinkler heads can be replaced with heads that comply with NCSE 032 (Systems isolated at 2131 [CST] on 2/3/11)."
"At 0930 CST on 02-03-11, the Plant Shift Superintendent (PSS) was notified that a steam condensate line broke above the C-310 withdrawal room and water leaked through the ceiling into the withdrawal room on the ground floor. Water accumulated greater than 0.5 inch in depth in the diked area above the withdrawal room in violation of NCSA [Nuclear Criticality Safety Approval] 310-004. NCSA 310-004 requires that open containers with volumes greater than 5.5 gallons shall not contain pre-existing moderator greater than 0.5 inches in depth. During the walk down, it was discovered that the sprinkler heads currently installed above the withdrawal room are rated at 160F in violation of the NCS [Nuclear Criticality Safety] limit. NCSE [Nuclear Criticality Safety Evaluation] 032 requires the minimum activation temperature to be no lower than 200F. The sprinkler system was taken out of service and drained at 2131 CST on 02-03-11 and the level of water accumulated in the diked area was verified to be less than 0.5 inches at 0426 CST on 02-04-11.
"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.
"The NRC Senior Resident Inspector has been notified of this event.
SAFETY SIGNIFICANCE OF EVENTS
"The first leg of double contingency is based on preventing a release of fissile material greater than the safe mass of uranium. This event did not release fissile material greater than the safe mass of uranium.
POTENTIAL CRITICALITY PATHWAYS (BRIEF SCENARIO(S) OF HOW CRITICALITY COULD OCCUR)
"In order for a criticality to be possible, a large UF6 release containing greater than a critical mass of uranium would have to occur and accumulate greater than the critical configuration.
CONTROLLED PARAMETERS (MASS, MODERATION, GEOMETRY, CONCENTRATION, ETC.)
"The two process conditions relied upon for double contingency are mass and geometry.
ESTIMATED AMOUNT, ENRICHMENT, FORM OF MATERIAL (INCLUDE PROCESS LIMIT AND % WORST CASE CRITICAL MASS)
"Product withdrawal assay at the time of the event was less than 4.95 wt% U235. However, no UF6 release occurred.
NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES
"The first leg of double contingency is based on preventing a release of fissile material greater than the safe mass of uranium. Since a UF6 release containing greater than the safe mass has not occurred, the mass parameter has maintained. The second leg of double contingency limiting moderating liquids in open containers to less than 0.5 inches and requiring the sprinkler head activation temperature to greater than 200F. Since the diked area above the withdrawal room did accumulate water level greater than 0.5 inches, the control was violated. Additionally, since the installed sprinkler heads activation temperature is less than 200F, a design feature of NCSE 032 was violated. Therefore, double contingency was not maintained.
CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED
"Shiftly checks of the diked area above the withdrawal have been initiated to ensure water level is not accumulating. The condensate leak above the withdrawal room was repaired and solution level verified to be less than 0.5 inches (0426 [CST] on 2/4/11). The sprinkler systems associated with the sprinkler heads above the withdrawal room have been isolated until the sprinkler heads can be replaced with heads that comply with NCSE 032 (Systems isolated at 2131 [CST] on 2/3/11)."
Power Reactor
Event Number: 46591
Facility: COOPER
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: JERRY BEBB
HQ OPS Officer: STEVE SANDIN
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: JERRY BEBB
HQ OPS Officer: STEVE SANDIN
Notification Date: 02/03/2011
Notification Time: 17:54 [ET]
Event Date: 02/03/2011
Event Time: 08:58 [CST]
Last Update Date: 02/03/2011
Notification Time: 17:54 [ET]
Event Date: 02/03/2011
Event Time: 08:58 [CST]
Last Update Date: 02/03/2011
Emergency Class: NON EMERGENCY
10 CFR Section:
26.719 - FITNESS FOR DUTY
10 CFR Section:
26.719 - FITNESS FOR DUTY
Person (Organization):
LINDA HOWELL (R4DO)
LINDA HOWELL (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
FITNESS FOR DUTY REPORT INVOLVING A NON-LICENSED SUPERVISOR
A non-licensed employee supervisor had a confirmed positive for alcohol during a for cause fitness-for-duty test. The employee's access to the plant has been suspended. Contact the Headquarters Operations Officer for additional details.
The licensee informed the NRC Resident Inspector.
A non-licensed employee supervisor had a confirmed positive for alcohol during a for cause fitness-for-duty test. The employee's access to the plant has been suspended. Contact the Headquarters Operations Officer for additional details.
The licensee informed the NRC Resident Inspector.