ML052860133
| ML052860133 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 10/03/2005 |
| From: | Hutton J Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP1L 1987 | |
| Download: ML052860133 (2) | |
Text
Constellation Energy, Nine Mile Point Nuclear Station P.O. Box 63 Lycoming, NY 13093 October 3, 2005 NMP1L 1987 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001
SUBJECT:
Nine Mile Point Unit 1 Docket No. 50-220 Facility Operating License No. DPR-63 Special Report, Channel #12 of the Containment Hydrogen Monitoring System Inoperable Gentlemen:
In accordance with Action 4.a of Nine Mile Point Unit 1 Technical Specification Table 3.6.11-2, "Accident Monitoring Instrumentation Action Statements," Nine Mile Point Nuclear Station, LLC, is submitting the following Special Report concerning inoperability of Channel #12 of the Containment Hydrogen Monitoring (CHM) System.
Description of Event On September 19, 2005, at 0755 hours0.00874 days <br />0.21 hours <br />0.00125 weeks <br />2.872775e-4 months <br />, operators declared Channel #12 of the CHM System inoperable when the system was removed from service to support required surveillance testing.
At 1156 hours0.0134 days <br />0.321 hours <br />0.00191 weeks <br />4.39858e-4 months <br />, during the performance of the surveillance test, it was discovered that the high hydrogen and oxygen level annunciators and associated alarm lamps did not operate when required during testing.
The redundant Channel #11 of the CHM System was verified to be operable prior to removal of Channel #12 from service.
Page 2 NMP1L 1987 Cause of Inonerabilitv During performance of Channel #12 CHM System functional test, the high hydrogen and oxygen level annuciators failed to alarm in the control room as expected. The associated main system control hydrogen and oxygen alarm lamps also failed to illuminate as expected. The cause was determined to be a failed time delay relay.
Actions Taken The failed relay was replaced and post maintenance testing was completed satisfactorily.
Channel #12 of the CHM System was restored to operable status on September 19, 2005, at 1700 hours0.0197 days <br />0.472 hours <br />0.00281 weeks <br />6.4685e-4 months <br />.
Very truly yours, JAH/RF/sac Attachment cc:
Mr. S. J. Collins, NRC Regional Administrator, Region I Mr. G. K. Hunegs, NRC Senior Resident Inspector