United States Nuclear Regulatory Commission - Protecting People and the Environment

Event Notification Report for January 31, 2012

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
01/30/2012 - 01/31/2012

** EVENT NUMBERS **


47527 47624 47625 47626

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!!!!! THIS EVENT HAS BEEN RETRACTED. THIS EVENT HAS BEEN RETRACTED !!!!!
Agreement State Event Number: 47527
Rep Org: MA RADIATION CONTROL PROGRAM
Licensee: MASACHUSETTS INSTITUTE OF TECHNOLOGY
Region: 1
City: CAMBRIDGE State: MA
County:
License #:
Agreement: Y
Docket:
NRC Notified By: ANTHONY CARPENTINO
HQ OPS Officer: PETE SNYDER
Notification Date: 12/15/2011
Notification Time: 11:43 [ET]
Event Date: 12/14/2011
Event Time: [EST]
Last Update Date: 01/30/2012
Emergency Class: NON EMERGENCY
10 CFR Section:
AGREEMENT STATE
Person (Organization):
HAROLD GRAY (R1DO)
KEVIN O'SULLIVAN (FSME)

Event Text

AGREEMENT STATE REPORT - POSSIBLE EXTREMITY DOSE EXCEEDING ANNUAL LIMIT

"On 12/14/11, the licensee reported to Agency [Ma. Radiation Control Program] a potential dose exceeding the adult occupational shallow dose equivalent limit of 50 Rem to the extremities. Situation involved a researcher handling microcurie quantities of phosphorus-32. Licensee's initial estimate of worker extremity exposure is in the range of 47-59 rem during the previous six months. Worker monitored with a whole body dosimeter but not with an extremity dosimeter. Licensee investigation of researcher's experimental procedures and handling techniques, after researcher observed left index finger skin discoloration, led to the conclusion of potential dose exceeding annual regulatory limit. Individual restricted from further radioactive material handling. Experimental procedure changes implemented by licensee.

"An investigation is ongoing."

MA Event: 12-9924

* * * UPDATE FROM TONY CARPENITO TO VINCE KLCO AT 1132 EST ON 12/21/2011* * *

The following information was received from the Commonwealth by email:

"On 12/19/11, the licensee reported a revised worker extremity exposure estimate of 40.15 rem. The Commonwealth [Massachusetts Radiation Control Program] considers this event to still be open."

Notified the R1DO (Perry) and the FSME EO (Burgess).

* * RETRACTION FROM TONY CARPENTINO TO JOE O'HARA AT 0955 EST ON 1/30/2012 * *

"The Agency [Commonwealth of Massachusetts] inspection of 1/13/12 consisted of interviews with subject worker and other licensee personnel, observation of subject work area, and review of reports and representative records. Licensee determined subject worker's assigned 2011 shallow dose equivalent to the extremity to be 43.41 rem. Agency and subject worker accepts licensee's determination that subject worker's exposure did not exceed annual occupational dose limit for adults. Skin discoloration no longer visible.

"The Agency considers this event to be NON-REPORTABLE and CLOSED."

Notified R1DO(Cook) and FSME EO(McIntosh)

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Power Reactor Event Number: 47624
Facility: BYRON
Region: 3 State: IL
Unit: [ ] [2] [ ]
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: LEO WEHNER
HQ OPS Officer: JOHN KNOKE
Notification Date: 01/30/2012
Notification Time: 11:39 [ET]
Event Date: 01/30/2012
Event Time: 10:01 [CST]
Last Update Date: 01/30/2012
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(2)(i) - PLANT S/D REQD BY TS
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
JAMNES CAMERON (R3DO)
CYNTHIA PEDERSON (R3)
BRUCE BOGER (ET)
JEFFERY GRANT (IRD)
SIL MOUVONE (DOE)
DEBBY HASSEL (DHS)
LOU BURCKANT (FEMA)
SAM WILLIS (HHS)
MIKE BEVERLY (USDA)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
2 A/R Y 100 Power Operation 0 Hot Standby

Event Text

UNUSUAL EVENT DUE TO LOSS OF OFFSITE POWER GREATER THAN 15 MINUTES

At 1101 EST, Byron Unit-2 experienced a reactor trip due to RCP undervoltage. All rods fully inserted, MSIV's were manually closed and decay heat is being removed by Auxiliary Feedwater pumps running and steam leaving via atmospheric relief valves. The unit is currently in a natural circulation cooldown with the diesels supplying station emergency loads. Licensee will be cooling the plant down to Mode 5.

At 1118 EST, Byron declared an Unusual Event due to a loss of offsite power on Unit 2 from a faulted Station Auxiliary Transformer (SAT). The faulted SAT caused both 6.9 kV and 4.1 kV bus voltage to drop. Smoke was observed coming from the SAT with no visible flames being apparent. This caused bus loads to trip without a complete loss of ESF busses 241 and 242. These buses were manually disconnected from the SAT, which transferred the load to the emergency diesel generators 2A and 2B. Both diesel generators started and loaded without incident. Offsite assistance was requested from the local fire department as a precaution.

The licensee is also declaring notification for 10 CFR 50.72(b)(3)(v)(D) and 10 CFR 50.72(b)(3)(xi).

Unit 1 is not being affected by this event and remains at 100% power.

The licensee has notified the NRC Resident Inspector.

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Research Reactor Event Number: 47625
Facility: UNIV OF TEXAS
RX Type: 1100 KW TRIGA MARK II
Comments:
Region: 4
City: AUSTIN State: TX
County: TRAVIS
License #: R-129
Agreement: Y
Docket: 05000602
NRC Notified By: PAUL WHALEY
HQ OPS Officer: JOHN KNOKE
Notification Date: 01/30/2012
Notification Time: 16:02 [ET]
Event Date: 01/27/2012
Event Time: 11:16 [CST]
Last Update Date: 01/30/2012
Emergency Class: NON EMERGENCY
10 CFR Section:
NON-POWER REACTOR EVENT
Person (Organization):
JEFF CLARK (R4DO)
PAULETTE TORRES (NRR)

Event Text

TECHNICAL SPECIFICATION VIOLATION DISCOVERED

The licensee has determined that technical specification 6.5.2 was violated.

"The annual maintenance outage was conducted during the first two weeks in January 2012, with the biennial fuel inspection occupying most of the effort during the outage. On January 11th, the instrumented fuel elements were disconnected from the safety system for routine biennial surveillance which tests for unacceptable changes in fuel element length and bend. The surveillance was completed and the safety system restored on the same day. Maintenance was completed and normal operations resumed on January 23rd. Two non-routine maintenance items remain to be completed, installation of a 3rd safety channel calibrated to provide indication in the range where the safety limit is challenged, and replacement of an instrument rack in the control room to accommodate additional equipment supporting a facility security upgrade.

"On Monday January 23rd, the reactor was operated to support experiment operations coincident with reactor operator training. The preoperational checkout indicated satisfactory operation of the safety system, including the fuel temperature channels. Shutdown fuel temperatures were within tolerance for ambient conditions. Preoperational checks were completed at 9:32, with startup to 50 watts initiated at 09:33. Critical checks at 50 watts were accomplished at 9:33, followed by ascension to 100 kW at 10:00. Records of 100 kW operating data (status window print files) indicated 18?C on fuel temperature channel 1 and 83?C on fuel temperature channel 2; the senior reactor operator who performed the operation did not recognize the difference in temperature. The reactor was shutdown on completion of the experiment at 10:40.

"The next operation occurred on January 27th. Shutdown fuel temperatures were within tolerance for ambient conditions. Preoperational checks were completed at 9:09 with 50 watt critical data obtained at 9:13. Reactor power of 100 kW was achieved at 9:21, and 500 kW at 9:54. Records (status window print files) show fuel temperature channel 1 did not change from approximately 18?C at 100 kW and 500 kW. The senior reactor operator who performed the operation did not recognize the difference in temperature between fuel channel 1 and fuel channel 2. The reactor was shutdown at 11:16. Prior to a planned startup, the minor deviation between fuel temperatures at shutdown was noted to be unusual which prompted recognition of the previous 500 kW operating temperature. A preoperational check was performed, with no indication of abnormalities. Operations were terminated for investigation.

"INVESTIGATION

"The output of the thermocouple at fuel temperature channel 1, and was noted to be erratic when the wires at the pool side terminal were moved. It was noted that the nylon braid insulation was frayed and the black electricians tape around the lead wire was degraded. Resistance readings confirmed that perturbing the thermocouple lead wire causes the resistance of the detector loop to vary erratically, and that an alternate thermocouple loop is stable when the wires are moved.

"A functional response test was performed using the chill water system to cool the pool below ambient, and fuel temperature 2 was observed to fall significantly below ambient (about 13?C ) while fuel temperature channel 1 dropped slightly, to about 17?C. There are three thermocouples in each instrumented fuel element, although the fuel temperature monitoring channel uses only one of the three. Fuel channel 1 temperature monitoring channel was connected to an alternate thermocouple and the indication came into agreement with fuel temperature channel 2 and the pool water temperature channel.

"The plug and socket connector for fuel channel 1 was inspected, and it was noted that the wires entering the plug were frayed, facilitating a short circuit and an alternate thermocouple junction. It is not possible to unambiguously identify the short circuit path, but there is a metal identification tag, and a metal strain relief device that are in contact with the thermocouple lead wire assembly. Therefore the thermocouple junction being sensed by fuel temperature channel 1 was an inadvertent connection at the plug, sensing ambient air temperature. The wires at the fuel temperature channel 2 plugs were fabricated with sleeves over the wires, preserving the insulation, providing additional electrical isolation between the wires, and preventing sharp bends in the wires.

"At this point, an alternate thermocouple has been connected to fuel temperature channel 1, resistance readings indicate no short circuits, and the laboratory Director is preparing a restart letter with compensatory measures to be implemented pending development of permanent corrective action."

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Power Reactor Event Number: 47626
Facility: NORTH ANNA
Region: 2 State: VA
Unit: [1] [2] [ ]
RX Type: [1] W-3-LP,[2] W-3-LP
NRC Notified By: ROGER SMUTHERS
HQ OPS Officer: JOHN KNOKE
Notification Date: 01/30/2012
Notification Time: 19:15 [ET]
Event Date: 01/30/2012
Event Time: 18:56 [EST]
Last Update Date: 01/30/2012
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED
Person (Organization):
BRIAN BONSER (R2DO)
VICTOR MCCREE (RA)
ERIC LEEDS (ET)
JEFF GRANT (IRD)
BRUCE BOGER (NRR)
SCOTT MORRIS (IRD)
WILLIAM GOTT (IRD)
HILL (DHS)
BISCOE (FEMA)

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

Event Text

UNUSUAL EVENT DECLARED DUE TO AN EARTHQUAKE OF MAGNITUDE 3.2

At 1856 EST, North Anna, Units 1 and 2, experienced an onsite seismic event. This was confirmed by the National Earthquake Information Center to be a magnitude 3.2. Based on these 2 indications the licensee declared an Unusual Event per EAL HU 1.1. The earthquake did not impact operations or equipment, and both units remain at 100% power. To exit the Unusual Event the licensee will need to verify that no damage was sustained to any systems or equipment. Presently the licensee is conducting a walkdown to verify no damage was incurred.

The licensee has notified the NRC Resident Inspector. The licensee also notified the state and other government agencies.

* * * UPDATE AT 0048 EST ON 1/31/12 FROM ROGER SMUTHERS TO PETE SNYDER * * *

"The NOUE declared at 1856 EST on 1/30/12 has been terminated [at 0035 EST]. The event has been terminated after completion of AP-36, which is the procedure used when seismic activity is experienced. The abnormal procedure included engineering and operations inspections of various systems throughout the station, all of which were completed satisfactorily with no damage found relating to the seismic event."

"None of the stations seismic instrumentation actuated during the event due to low seismic activity felt at the station. The newly installed Free Field Seismic Instrumentation did not actuate which has a trigger point of 0.1 g's further demonstrating the low level of the seismic activity experienced at the station."

The licensee notified the NRC Resident Inspector. Notified R2DO (Bonser), NRR (Lund), IRD (Grant), DHS (Gates), and FEMA (Biscoe).

Page Last Reviewed/Updated Thursday, March 29, 2012
Thursday, March 29, 2012