Event Notification Report for May 15, 2016
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
05/14/2016 - 05/15/2016
Power Reactor
Event Number: 51929
Facility: MILLSTONE
Region: 1 State: CT
Unit: [] [] [3]
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: MICHAEL CICCONE
HQ OPS Officer: DONALD NORWOOD
Region: 1 State: CT
Unit: [] [] [3]
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: MICHAEL CICCONE
HQ OPS Officer: DONALD NORWOOD
Notification Date: 05/15/2016
Notification Time: 07:08 [ET]
Event Date: 05/15/2016
Event Time: 06:38 [EDT]
Last Update Date: 05/15/2016
Notification Time: 07:08 [ET]
Event Date: 05/15/2016
Event Time: 06:38 [EDT]
Last Update Date: 05/15/2016
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
Person (Organization):
ART BURRITT (R1DO)
DAVID LEW (R1DR)
BRIAN MCDERMOTT (NRR)
JEFFERY GRANT (IRD)
SCOTT MORRIS (NRR)
ART BURRITT (R1DO)
DAVID LEW (R1DR)
BRIAN MCDERMOTT (NRR)
JEFFERY GRANT (IRD)
SCOTT MORRIS (NRR)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 3 | M/R | Y | 100 | Power Operation | 0 | Hot Standby |
UNUSUAL EVENT DUE TO MAIN GENERATOR HYDROGEN LEAK IN TURBINE BUILDING
At 0638 EDT on 5/15/2016, an Unusual Event (EAL GU.2) was declared on Millstone Unit 3 due to a Main Generator hydrogen gas leak into the Turbine Building. At 0645 EDT, operators manually tripped the reactor. All rods inserted. All systems functioned as expected following the reactor trip. Operators are currently venting the remaining hydrogen from the generator through the normal vent path. There is no safety related equipment out-of-service. The plant is in a normal post-trip electrical line-up. All Emergency Diesel Generators are available.
The licensee notified the State of Connecticut and the NRC Resident Inspector.
Notified DHS SWO, FEMA Ops Center, and DHS NICC Watch Officer. Notified via E-mail FEMA National Watch Center and NuclearSSA.
* * * UPDATE FROM MIKE CICCONE TO HOWIE CROUCH AT 1044 EDT ON 5/15/16 * * *
At 0949 EDT, the licensee terminated the Unusual Event.
"At 0645 EDT on 5/15/16, a manual reactor trip was initiated at Millstone Unit 3 due to a hydrogen leak from the main generator. As expected, Auxiliary Feedwater System (AFW) initiated on the reactor trip. The trip was uncomplicated and the plant is currently in Mode 3 with a normal electric lineup and decay heat is being removed via steam dumps to the condenser. The cause of the hydrogen leakage is under investigation. This is reportable under 10 CFR 50.72(b)(2)(iv)(B) - RPS actuation while critical, and 10 CFR 50.72 (b)(3)(iv)(A) - valid specified system actuation."
The licensee has notified Waterford Township, the State of Connecticut and the NRC Resident Inspector.
Notified R1DO (Burritt), NRR ET (McDermott), NRR EO (Morris), IRD (Grant), DHS SWO, FEMA Ops Center, DHS NICC, FEMA National Watch Center (email) and NuclearSSA (email).
At 0638 EDT on 5/15/2016, an Unusual Event (EAL GU.2) was declared on Millstone Unit 3 due to a Main Generator hydrogen gas leak into the Turbine Building. At 0645 EDT, operators manually tripped the reactor. All rods inserted. All systems functioned as expected following the reactor trip. Operators are currently venting the remaining hydrogen from the generator through the normal vent path. There is no safety related equipment out-of-service. The plant is in a normal post-trip electrical line-up. All Emergency Diesel Generators are available.
The licensee notified the State of Connecticut and the NRC Resident Inspector.
Notified DHS SWO, FEMA Ops Center, and DHS NICC Watch Officer. Notified via E-mail FEMA National Watch Center and NuclearSSA.
* * * UPDATE FROM MIKE CICCONE TO HOWIE CROUCH AT 1044 EDT ON 5/15/16 * * *
At 0949 EDT, the licensee terminated the Unusual Event.
"At 0645 EDT on 5/15/16, a manual reactor trip was initiated at Millstone Unit 3 due to a hydrogen leak from the main generator. As expected, Auxiliary Feedwater System (AFW) initiated on the reactor trip. The trip was uncomplicated and the plant is currently in Mode 3 with a normal electric lineup and decay heat is being removed via steam dumps to the condenser. The cause of the hydrogen leakage is under investigation. This is reportable under 10 CFR 50.72(b)(2)(iv)(B) - RPS actuation while critical, and 10 CFR 50.72 (b)(3)(iv)(A) - valid specified system actuation."
The licensee has notified Waterford Township, the State of Connecticut and the NRC Resident Inspector.
Notified R1DO (Burritt), NRR ET (McDermott), NRR EO (Morris), IRD (Grant), DHS SWO, FEMA Ops Center, DHS NICC, FEMA National Watch Center (email) and NuclearSSA (email).
Power Reactor
Event Number: 51931
Facility: BYRON
Region: 3 State: IL
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: RICARDO ROSAS
HQ OPS Officer: VINCE KLCO
Region: 3 State: IL
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: RICARDO ROSAS
HQ OPS Officer: VINCE KLCO
Notification Date: 05/15/2016
Notification Time: 12:34 [ET]
Event Date: 05/15/2016
Event Time: 11:18 [CDT]
Last Update Date: 05/15/2016
Notification Time: 12:34 [ET]
Event Date: 05/15/2016
Event Time: 11:18 [CDT]
Last Update Date: 05/15/2016
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(xi) - OFFSITE NOTIFICATION
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
ERIC DUNCAN (R3DO)
CYNTHIA PEDERSON (RA3)
BILL DEAN (NRR)
JEFF GRANT (IRD)
ERIC DUNCAN (R3DO)
CYNTHIA PEDERSON (RA3)
BILL DEAN (NRR)
JEFF GRANT (IRD)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Hot Standby | 0 | Hot Standby |
UNUSUAL EVENT DECLARED DUE TO EXCESSIVE UNIDENTIFIED LEAKAGE DURING PLANT STARTUP
"Unit 2 experienced RCS Leakage, potentially pressure boundary leakage, or Unidentified Leakage greater than 10 gpm for [greater than] 15 minutes. Reactor Vessel Flange Temperature High Leakoff alarm was received. This met threshold for declaration of an Unusual Event at 1118 CDT per MU6. Unit 2 is currently in MODE 3. Investigation is in progress to identify specific leakage location."
The plant is stable, leakage indicates about 32 gpm and the startup has been stopped. There is no impact on Unit 1.
The licensee notified the NRC Resident Inspector and State authorities.
Notified DHS SWO, FEMA Ops Center, DHS NICC,. Notified FEMA National Watch and Nuclear SSA via email.
* * * UPDATE FROM RICARDO ROSAS TO VINCE KLCO ON 5/15/16 AT 1626 EDT * * *
"At 1459 CDT, the conditions under MU6 are no longer met. The site has terminated the Unusual Event. In addition, a press release will be made of this event."
Unit 2 is stable and in Mode 3 pending further evaluation. The leak stopped when a loop drain isolation valve was closed.
The licensee notified the NRC Resident Inspector and State and local authorities.
Notified the R3DO (Duncan), NRR EO (Morris), IRD MOC (Grant), DHS SWO, FEMA Ops Center, and DHS NICC. Notified the FEMA National Watch and Nuclear SSA via email.
"Unit 2 experienced RCS Leakage, potentially pressure boundary leakage, or Unidentified Leakage greater than 10 gpm for [greater than] 15 minutes. Reactor Vessel Flange Temperature High Leakoff alarm was received. This met threshold for declaration of an Unusual Event at 1118 CDT per MU6. Unit 2 is currently in MODE 3. Investigation is in progress to identify specific leakage location."
The plant is stable, leakage indicates about 32 gpm and the startup has been stopped. There is no impact on Unit 1.
The licensee notified the NRC Resident Inspector and State authorities.
Notified DHS SWO, FEMA Ops Center, DHS NICC,. Notified FEMA National Watch and Nuclear SSA via email.
* * * UPDATE FROM RICARDO ROSAS TO VINCE KLCO ON 5/15/16 AT 1626 EDT * * *
"At 1459 CDT, the conditions under MU6 are no longer met. The site has terminated the Unusual Event. In addition, a press release will be made of this event."
Unit 2 is stable and in Mode 3 pending further evaluation. The leak stopped when a loop drain isolation valve was closed.
The licensee notified the NRC Resident Inspector and State and local authorities.
Notified the R3DO (Duncan), NRR EO (Morris), IRD MOC (Grant), DHS SWO, FEMA Ops Center, and DHS NICC. Notified the FEMA National Watch and Nuclear SSA via email.