ML12173A367
| ML12173A367 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 06/21/2012 |
| From: | Krohn P G Reactor Projects Region 1 Branch 4 |
| To: | |
| KROHN, PG | |
| References | |
| PNO-I-12-003 | |
| Download: ML12173A367 (2) | |
Text
Date: June 21, 2012
PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-I-12-003 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. Some of the information received may not yet be fully verified or evaluated by the Region Staff.
Facility Licensee Emergency Classification PPL Susquehanna, LLC Susquehanna Unit 1 Berwick, PA Docket: 50-387 Notification of Unusual Event Alert Site Area Emergency General Emergency X Not Applicable
SUBJECT:
SHUTDOWN EXPECTED TO BE GREATER THAN 72 HOURS TO REPAIR A LEAK FROM A CHEMICAL DECONTAMINATION PIPE ON THE '1A' REACTOR RECIRCULATION LOOP The licensee for Susquehanna Unit 1 commenced an unplanned shutdown on June 19 to conduct an inspection to identify the source of a leak into the drywell. The leakage had increased from 0.13 gallons per minute (gpm) to 1.62 gpm over a 4 day period.
The licensee identified a leak in reactor coolant pressure boundary piping in the weld for a decontamination connection on the '1A' reactor recirculation loop. The leak occurred in the weld where the decontamination pipe is connected to the 28 inch diameter reactor recirculation suction line. The decontamination connection, which is sealed with a bolted blank flange/cover during plant operations, is a pipe approximately 10 inches long and 4 inches in diameter. This pipe is welded to the reactor coolant system piping on the suction side of the '1A' reactor recirculation pump. The connection is designed to be used on an infrequent basis during outage periods to decontaminate the reactor coolant system piping.
The licensee took the plant to cold shutdown to repair the leak. The licensee is currently developing plans for repairing the weld, performing extent of condition inspections, and conducting a root cause analysis of the cracked weld. The Resident Inspectors and a Regional specialist will continue to review the circumstances surrounding the event.
The NRC Resident Inspectors monitored the shutdown and will continue to evaluate the shutdown, repair activities, and corrective actions.
The information presented herein has been discussed with PPL Susquehanna management and is current as of June 20, 2012.
The Commonwealth of Pennsylvania has been notified.
Region I Public Affairs is prepared to respond to media inquiries.
ADAMS Accession Number: ML12173A367
CONTACT: Paul G. Krohn (610) 337-5120
ML12173A367 SUNSI Review Non-Sensitive Sensitive Publicly Available Non-Publicly Available OFFICE RI/DRP RI/SLO RI/PAO RI/ORA RI/DRP RI/ORA NAME PKrohn/PGK NMcNamara/NM DScrenci /DS ADeFrancisco/ADef DRoberts/JWC for WDean/ADef for DATE 06/20 /12 06/20 /12 06/20 /12 06/ 21/12 0621 /12 06/21/12