PNO-III-09-013, D. C. Cook Unit 1 Mode Change Following 14 Months Forced Outage
| ML093270266 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 11/23/2009 |
| From: | Jamnes Cameron, Wright G NRC/RGN-III/DRP/B6 |
| To: | |
| References | |
| PNO-III-09-013 | |
| Download: ML093270266 (1) | |
PRELIMINARY NOTIFICATION-REGION III November 23, 2009 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-III-09-013 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region III staff on this date.
Facility Donald C. Cook Nuclear Plant Indiana Michigan Power Company Stevensville, MI Docket: 50-315 License: DPR-58 Licensee Emergency Classification Notification of Unusual Event Alert Site Area Emergency General Emergency X Not Applicable
SUBJECT:
D.C. COOK UNIT 1 MODE CHANGE FOLLOWING 14 MONTHS FORCED OUTAGE DESCRIPTION:
On November 21, 2009, at approximately 2:30 p.m. EST, D.C. Cook Nuclear Plant Unit 1 transitioned from Mode 5 to Mode 4 in preparation for the units restart following a 14 month forced outage. On September 20, 2008, a malfunction in the Unit 1 main turbine generator (TG) led to high vibrations that caused operators to manually trip the Unit 1 reactor and TG and to break main condenser vacuum. A TG hydrogen fire resulted when the catastrophic turbine failure caused hydrogen seals to fail. Refer to PNO-III-08-011 (ML082660516)
Over the past 14 months, the licensee has repaired all four sections of the main turbine rotor, the turbine casings, the main generator, and the turbine foundation sole plates along with other collateral damage to equipment caused by the turbine failure. Modifications to the low pressure turbine rotors were also made to allow for operation until the rotors are replaced using a different design.
The resident inspectors have been monitoring the licensee activities. In addition, focused inspections have been conducted by the residents and regional based inspectors to assess the licensees repair activities.
The State of Michigan has been informed.
The information in this preliminary notification has been reviewed with licensee management and is current as of 8:00 a.m. (CST) November 23, 2009.
CONTACTS:
Geoffrey C. Wright Jamnes L. Cameron ML093270266 630/829-9602 630/829-9833