| U.S. Nuclear Regulatory Commission
Operations Center Event Reports For
03/06/2015 - 03/09/2015 ** EVENT NUMBERS ** |
 | Power Reactor | Event Number: 50866 | Facility: PRAIRIE ISLAND
Region: 3 State: MN
Unit: [ ] [2] [ ]
RX Type: [1] W-2-LP,[2] W-2-LP
NRC Notified By: DARRELL LAPCINSKI
HQ OPS Officer: STEVE SANDIN | Notification Date: 03/05/2015
Notification Time: 05:35 [ET]
Event Date: 03/05/2015
Event Time: 04:06 [CST]
Last Update Date: 03/06/2015 | Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED
| Person (Organization):
KENNETH RIEMER (R3DO)
MARY JANE ROSS-LEE (NRR)
CYNTHIA PEDERSON (RA)
BILL DEAN (ET)
BERNARD STAPLETON (IRD)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 2 | N | Y | 100 | Power Operation | 92 | Power Operation | Event Text UNIT 2 DECLARES UNUSUAL EVENT DUE TO INABILITY TO VALIDATE A CONTAINMENT FIRE ALARM WITHIN 15 MINUTES
"The Instrument Air Containment Isolation failed closed on Unit 2. This isolated normal letdown / excess letdown and required Pressurizer level to be maintained by diverting Pressurizer level to the Pressurizer Relief Tank. The Pressurizer Relief Tank rupture disc ruptured which resulted in a fire alarm in Unit 2 Containment. The fire alarm could not be validated within 15 minutes which resulted in a declaration of an Unusual Event based on EAL HU2.1. The loss of Instrument Air to Unit 2 Containment resulted in a loss of cooling to the reactor vessel gap and support cooling systems. Due to the loss of reactor vessel ventilation systems a plant shutdown to Mode 3 has been initiated. No radioactive releases to the environment are in progress or expected to occur. The public health and safety has not been jeopardized."
The licensee informed state/local agencies and the NRC Resident Inspector and does plan to issue a press release.
Notified other Federal Agencies (DHS SWO, FEMA Ops, FEMA NWC, NICC Watch Officer and NuclearSSA).
* * * UPDATE AT 0130 EST ON 03/06/15 FROM TERRY BACON TO DANIEL MILLS * * *
"At 1725 [CST] on 3/5/15 Instrument Air to Unit 2 containment was established. Letdown was then reestablished. These actions stabilized the plant and stopped the 30 GPM [gallons per minute] identified leakage out of the PZR Relief Tank rupture disc into containment. This condition is what caused the fire detection alarm in containment, and is also Unusual Event criteria. Unit 2 containment was entered and it was confirmed that NO fire existed in containment. The Unusual Event was terminated at 0018 CST on 3/6/15 based on no fire and no identified RCS leakage into containment. The plant is currently in Mode 3. The health and safety of the public was not jeopardized."
The licensee informed state/local agencies and the NRC Resident Inspector and does plan to issue a press release.
Notified R3DO (Stone), EO (Ross-Lee) and IRD (Stapleton).
Notified other Federal Agencies (DHS SWO, FEMA Ops, FEMA NWC, NICC Watch Officer and NuclearSSA). |
| Power Reactor | Event Number: 50870 | Facility: PRAIRIE ISLAND
Region: 3 State: MN
Unit: [ ] [2] [ ]
RX Type: [1] W-2-LP,[2] W-2-LP
NRC Notified By: TERRY BACON
HQ OPS Officer: HOWIE CROUCH | Notification Date: 03/07/2015
Notification Time: 15:05 [ET]
Event Date: 03/07/2015
Event Time: 11:55 [CST]
Last Update Date: 03/07/2015 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(C) - POT UNCNTRL RAD REL
| Person (Organization):
KENNETH RIEMER (R3DO)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 2 | N | N | 0 | | 0 | | Event Text CONTAINMENT DECLARED INOPERABLE DUE TO CONTAINMENT FAN COIL LEAK
"At 1155 CST on March 7, 2015, a small cooling water leak was identified on the 21 Containment Fan Coil Unit east face u-bend on the north east corner bottom bundle. Unit 2 Containment was declared inoperable, which required entry into Technical Specifications (TS) LCO 3.6.1, Condition A, Containment inoperable, applicable in MODES 1, 2, 3, and 4. Immediate actions were taken to isolate the Fan Coil Unit within 1 hour from the initial identification of the leak. 21 Containment Fan Coil Unit was isolated, Containment was declared operable and TS 3.6.1 Condition A was exited at 1220 CST on 3/7/15.
"This condition is reportable under 10 CFR 50.72(b)(3)(v)(C) as an event or condition that could have prevented fulfillment of the safety function of structures or systems that are needed to control the release of radioactive material.
"The plant remains in a safe condition and there was no effect to the health and safety of the public.
"The licensee has notified the NRC Resident Inspector." |
| Research Reactor | Event Number: 50871 | Facility: NATIONAL INST OF STANDARDS & TECH
RX Type: 20000 KW TEST
Comments:
Region: 1
City: GAITHERSBURG State: MD
County: MONTGOMERY
License #: TR-5
Agreement: Y
Docket: 05000184
NRC Notified By: PAUL BRAND
HQ OPS Officer: HOWIE CROUCH | Notification Date: 03/07/2015
Notification Time: 16:55 [ET]
Event Date: 03/07/2015
Event Time: 08:30 [EST]
Last Update Date: 03/07/2015 | Emergency Class: NON EMERGENCY
10 CFR Section:
NON-POWER REACTOR EVENT
| Person (Organization):
XIAOSONG YIN (NRR)
ALEXANDER ADAMS (NRR)
PATRICK ISAAC (NRR)
KEVIN HSUEH (EMAIL) (NRR)
| Event Text LIMITING CONDITION FOR OPERATION NOT MET DUE TO EMERGENCY SUMP PUMP INOPERABLE
"On March 7, 2015, at 0830 EST, the NCNR (NIST Center for Neutron Research) discovered a probable violation of the Limiting Condition for Operations of the TR-5 Technical Specifications (TS), 3.3.2, Specification (1), while performing maintenance during the scheduled reactor shutdown period. This initial report is being made in accordance with TR-5 TS 6.7.2.d.
"The TS is as follows:
TS 3.3.2 Emergency Core Cooling; Specification: The reactor shall not be operated unless: (1) The D2O (deuterium oxide) emergency core cooling system is operable, and (2) A source of makeup water to the D2O emergency cooling tank is available.
"The discovery was made at 0830 EST on March 7, 2015, that the local disconnect switch for the emergency sump pump was in the disconnect position. The last time that it was verified operable was on July 2, 2014, when the annual surveillance of operability was performed. There was no maintenance performed on the emergency sump pump, nor is there any other known reason that the switch would have been placed in the disconnect position since July 2, 2014.
"After the discovery the sump pump disconnect switch was immediately placed in the connect position.
"The emergency core cooling system, in the event of loss of core coolant, provides sufficient D2O, to passively provide adequate coolant for ~ 2.5 hours to cool the fuel and protect against the release of fission products. That part of the emergency core cooling system was and remains operable and is not part of this violation.
"The emergency core cooling system employs one sump pump to return spilled coolant to the overhead storage tank. There is only enough D2O in the overhead storage tank to provide cooling for 2.5 hours on a once through basis. Because there is only one sump pump, it must be operational whenever the reactor is operational (TS 3.3.2 (1)). In the event that that pump fails or is inoperable and the D2O supply in the overhead storage tank is exhausted, domestic water or a suitable alternative would be used to furnish water for once through cooling (TS 3.3.2 (2)). A source of makeup water to the D2O emergency cooling tank was and remains available and is not part of this violation.
"The violation that is the subject of this report is that the sump pump was discovered inoperable and may have been inoperable since July 2, 2014, which includes periods of reactor operation. That is a violation of TS 3.3.2 (1)."
The licensee is conducting an investigation into this event. |
| Power Reactor | Event Number: 50872 | Facility: RIVER BEND
Region: 4 State: LA
Unit: [1] [ ] [ ]
RX Type: [1] GE-6
NRC Notified By: DANNY JAMES
HQ OPS Officer: DONALD NORWOOD | Notification Date: 03/08/2015
Notification Time: 05:21 [ET]
Event Date: 03/07/2015
Event Time: 21:40 [CST]
Last Update Date: 03/08/2015 | Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
| Person (Organization):
RAY KELLAR (R4DO)
|
| Unit | SCRAM Code | RX CRIT | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode | | 1 | N | N | 0 | Refueling | 0 | Refueling | Event Text SPECIFIED SYSTEM ACTUATION DUE TO LOSS OF ONE RESERVE STATION SERVICE OFFSITE POWER SOURCE
"On March 7, 2015, at 2140 CST, with the plant in Mode 5, Refueling, the RSS#2, one of two Reserve Station Service offsite power sources, de-energized. This loss of RSS#2 caused the de-energization of the Division 2 Safety Bus, which caused a valid start signal to the logic of the Division 2 Emergency Diesel Generator. No start occurred, however, due to the diesel being in the maintenance mode. Division 2 Standby Service Water, which was being run for system fill and vent as well as surveillance testing, also lost power.
"At the time RSS#2 was lost, the Division 2 Diesel generator and Division 2 Standby Service Water were inoperable for the Refuel Outage 18 Division 2 maintenance window.
"Division 1 systems and RSS#1 were not affected by the power loss and continued to operate normally. There were 5 control building dampers and 1 floor drain air operated valve that repositioned due to the loss of power.
"The cause of RSS#2 de-energization is still under investigation."
The licensee notified the NRC Resident Inspector. | |