PNO-I-11-003, A, Update: Nine Mile Point Unit 2 Notification of Unusual Event Due to Reactor Coolant System Leak Greater than 10 Gpm and Plant Shutdown Greater than Three Days
ML112270473 | |
Person / Time | |
---|---|
Site: | Nine Mile Point ![]() |
Issue date: | 08/15/2011 |
From: | Glenn Dentel Reactor Projects Branch 1 |
To: | |
Dentel, G RGN-I/DRP/BR1/610-337-5233 | |
References | |
PNO-I-11-003A | |
Download: ML112270473 (2) | |
Date: August 15, 2011 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-I-11-003A 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 Constellation Energy Nuclear Group, LLC Licensee Emergency Classification Nine Mile Point Unit 2 X Notification of Unusual Event Lycoming, NY Alert Docket: 50-410 Site Area Emergency General Emergency Not Applicable
SUBJECT:
UPDATE - NINE MILE POINT UNIT 2 NOTIFICATION OF UNUSUAL EVENT DUE TO REACTOR COOLANT SYSTEM LEAK GREATER THAN 10 GPM AND PLANT SHUTDOWN GREATER THAN THREE DAYS This preliminary notification supplements information in PNO-I-11-003, which documented an Unusual Event and plant shutdown due to a reactor coolant system leak greater than 10 gpm on August 6, 2011.
At 6:35 a.m., on August 10, Nine Mile Point operators commenced a Unit 2 plant startup, and the reactor was taken critical at 9:12 a.m. On August 11, at 12:16 a.m., Unit 2 was manually scrammed from 15 percent power, prior to synchronizing the main generator to the electrical grid. Approximately two hours earlier, operators had noted a leak from the A main feedwater pump minimum flow line. Before action could be taken to stop the leak, a vent line broke free, increasing leakage from the non-safety related feedwater system, and leading operators to the decision to manually scram the reactor. The leaking water was collected in the turbine building sump. During the scram, all control rods inserted and all systems functioned as designed.
Following repairs to the piping, Unit 2 was restarted on August 12. The reactor was taken critical at 5:45 a.m., and the generator was synchronized to the electrical grid at 4:21 p.m.
The NRC Resident Inspectors responded to the site after the shutdown to monitor Constellations response. The inspectors also evaluated repair activities and corrective actions prior to plant restart.
The information presented herein has been discussed with Nine Mile Point management and is current as of August 15, 2011, at 10:00 a.m.
State and local officials have been informed.
Region I Public Affairs is prepared to respond to media inquiries.
ADAMS Accession Number: ML112270473 CONTACT: Glenn Dentel (610) 337-5233
DISTRIBUTIONS:
BY E-MAIL:
OWFN TWFN Chairman Jaczko NMSS Comm. Svinicki OIG Comm. Apostolakis RES Comm. Magwood Comm. Ostendorff OIP OCA OGC OPA EDO OE NRR SECY IRO ACRS NSIR NRO PDR RSLO Regional Offices By Fax:
DOT:Trans INPO NSAC RI Resident Office Licensee: Constellation Energy Nuclear Group, LLC ADAMS Accession Number: ML112270473 SUNSI Review Complete: NMP (Reviewers Initials)
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