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Category:NRC Preliminary Notification of Event/Occurrence
MONTHYEARPNO-III-18-002, Beaver Valley, Davis-Besse, Perry Notification of Bankruptcy Filing by Firstenergy Solutions2018-04-0404 April 2018
PNO-III-18-002: Beaver Valley, Davis-Besse, Perry Notification of Bankruptcy Filing by Firstenergy Solutions
PNO-III-16-004, A - Unplanned Shutdown of Davis-Besse Nuclear Power Station for Greater than 72 Hours - Update2016-09-23023 September 2016
PNO-III-16-004A - Unplanned Shutdown of Davis-Besse Nuclear Power Station for Greater than 72 Hours - Update
ML16257A2032016-09-13013 September 2016
PNO-III-16-004, Davis-Besse Nuclear Power Station, Unplanned Shutdown for Greater than 72 Hours
PNO-III-15-006, Davis-Besse Shutdown Due to Secondary Side Steam Line Rupture2015-05-13013 May 2015
PNO-III-15-006: Davis-Besse Shutdown Due to Secondary Side Steam Line Rupture
PNO-III-14-003, A - Update to Davis-Besse Shield Building Restoration2014-04-28028 April 2014
PNO-III-14-003A - Update to Davis-Besse Shield Building Restoration
ML14050A0262014-02-19019 February 2014
PNO-III-14-003: Davis-Besse Shield Building Voids
PNO-III-13-007, Davis-Besse Shield Building Laminar Cracks2013-09-20020 September 2013
PNO-III-13-007 Davis-Besse Shield Building Laminar Cracks
PNO-III-13-006, A: Davis Besse Preliminary Notification Update Unplanned Shutdown Greater than 72 Hours on June 29, 2013, Due to Trip of Reactor Coolant Pump and Subsequent Discovery of Reactor Pressure Boundary Leakage2013-07-15015 July 2013
PNO-III-13-006A: Davis Besse Preliminary Notification Update Unplanned Shutdown Greater than 72 Hours on June 29, 2013, Due to Trip of Reactor Coolant Pump and Subsequent Discovery of Reactor Pressure Boundary Leakage
ML13184A1762013-07-0202 July 2013
PNO-III-13-006 - Davis Besse Unplanned Shutdown Greater than 72 Hours on June 26, 2013, Due to Trip of Reactor Coolant Pump and Subsequent Discovery of Reactor Pressure Boundary Leakage
PNO-III-11-014, Davis-Besse Shield Building Indications2011-10-20020 October 2011
PNO-III-11-014, Davis-Besse Shield Building Indications
PNO-III-10-011, DAVIS-BESSE Start-Up of Following Repairs of Control Rod Drive Mechanism Nozzle Flaw Indications2010-06-29029 June 2010
PNO-III-10-011 - DAVIS-BESSE Start-Up of Following Repairs of Control Rod Drive Mechanism Nozzle Flaw Indications
PNO-III-10-008, Davis-Besse, Public Availability of Two NRC Employee Differing Professional Opinions Concerning Past Issues at Davis-Besse2010-05-20020 May 2010
PNO-III-10-008: Davis-Besse, Public Availability of Two NRC Employee Differing Professional Opinions Concerning Past Issues at Davis-Besse
PNO-III-10-003, A - Davis-Besse Nuclear Power Station - Update - Davis-Besse Control Rod Drive Mechanism Nozzle Indications2010-04-12012 April 2010
PNO-III-10-003A - Davis-Besse Nuclear Power Station - Update - Davis-Besse Control Rod Drive Mechanism Nozzle Indications
ML1007503172010-03-16016 March 2010
PNO-III-10-003 - Davis-Besse Nuclear Power Station - Davis-Besse Control Rod Drive Mechanism Nozzle Indications
PNO-III-09-005, A: Davis-Besse, Transitory Alert Due to Electric Device Failure (Update)2009-06-29029 June 2009
PNO-III-09-005A: Davis-Besse, Transitory Alert Due to Electric Device Failure (Update)
ML0917706352009-06-26026 June 2009
PNO-III-09-005: Davis-Besse, Transitory Alert Due to Electric Device Failure
PNO-III-06-002, Security Event at Davis-Besse2006-01-23023 January 2006
PNO-III-06-002-Security Event at Davis-Besse
PNO-III-04-008, Davis Besse Issued 08/04/2004 Re Automatic Reactor Shutdown2004-08-0404 August 2004
PNO-III-04-008: Davis Besse Issued 08/04/2004 Re Automatic Reactor Shutdown
PNO-III-04-003, Shutdown of the Davis-Besse Nuclear Power Station Plant for Greater than 72 Hours2004-03-17017 March 2004
PNO-III-04-003: Shutdown of the Davis-Besse Nuclear Power Station Plant for Greater than 72 Hours
PNO-III-03-010, Davis Besse: Fuel Loading2003-02-21021 February 2003
PNO-III-03-010, Davis Besse: Fuel Loading
PNO-III-02-036, Crack Identified in Vessel Head Stainless Steel Liner2002-09-10010 September 2002
PNO-III-02-036: Crack Identified in Vessel Head Stainless Steel Liner
ML0308703762002-09-10010 September 2002
Preliminary Notification of Event or Unusual Occurrence -- PNO-III-02-036
PNO-III-02-016, A; Discrete Radioactive Particles Found Outside the Radiologically Restricted Area, Davis-Besse Update2002-04-24024 April 2002
PNO-III-02-016A; Discrete Radioactive Particles Found Outside the Radiologically Restricted Area, Davis-Besse Update
PNO-III-02-006, B, Davis Besse - Reactor Vessel Head Degradation (Second Update)2002-04-0505 April 2002
PNO-III-02-006B, Davis Besse - Reactor Vessel Head Degradation (Second Update)
ML0235800962002-03-11011 March 2002
E-mail from PN1 to Events, Front, PN1, PN302006, Davis-Besse - Update - Significant Metal Loss Observed in Reactor Vessel Head
2018-04-04
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PRELIMINARY NOTIFICATION March 16, 2010
PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE: PNO-III-10-003 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. Some of the information may not yet be fully verified or evaluated and is basically all that is known by the Region III staff on this date.
Facility Davis-Besse Nuclear Power Station First Energy Nuclear Operating Company Oak Harbor, Ohio Docket: 50-346
Licensee Emergency Classification Notification of Unusual Event Alert Site Area Emergency General Emergency x Not Applicable
Subject:
DAVIS-BESSE CONTROL ROD DRIVE MECHANISM NOZZLE INDICATIONS While performing NRC required inspections on Friday, March 12, Davis-Besse Nuclear Power Station (DBNPS) workers identified potential cracks in some of the control rod drive mechanism (CRDM) nozzles inspected. At the time DBNPS was conducting planned ultrasonic (UT) examinations on the CRDM nozzles which penetrate the reactor pressure vessel (RPV) head. The reactor is in a safe condition and has been shut down for a scheduled refueling outage since February 28, 2010.
Additionally, during the bare metal visual examination of the outer surface of the RPV head, dried boron deposits were found at two of the CRDM nozzles, which is indicative of possible primary water leakage. A visual examination and a UT examination is being performed on the RPV head. As of March 15, 2010, the utility has completed examinations on 50 of the 69 nozzles for the first set of planned UT examinations. When the utility is ready they will provide an action plan for the nozzle repair activities to the NRC.
The NRC Resident Inspectors continue to monitor the licensee's outage activities as well as the progress and outcome of the CRDM nozzle examinations and RPV head inspection. The NRC has sent additional inspectors from the Region III office to support the resident inspectors' review of the issues related to the RPV head. Experts from the Region bring detailed knowledge to the monitoring and oversight efforts.
The NRC will review the utility repair plan and conduct inspections as the repairs are being made before the plant can restart to ensure safe operation.
The State of Ohio has been notified.
This preliminary notification is issued for information only.
Region III received initial notification of this occurrence by a telephone call from the licensee at 4:45 a.m. (EST) on March 13, 2010 (refer to Event Notification 45764). The information presented herein has been discussed with the licensee, and is current as of 11:30 a.m. Central Daylight Savings Time, March 15, 2010.
ADAMS Accession Number: ML100750317 Contacts: J. Cameron D. Hills (630) 829-9833 (630) 829-9733 Jamnes.Cameron@nrc.gov David.Hills@nrc.gov
