ML043140297
| ML043140297 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 10/26/2004 |
| From: | O'Connor T Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP1L 1879 | |
| Download: ML043140297 (2) | |
Text
4-W Constellation Energy P.O. Box 63 Nine Mile Point Nuclear Station Lycoming, New York 13093 October 26, 2004 NMP1L 1879 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Nine Mile Point Unit 1 Docket No. 50-220 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 October 12, 2004, at 0956 hours0.0111 days <br />0.266 hours <br />0.00158 weeks <br />3.63758e-4 months <br />, Channel #12 of the CHM System was declared inoperable when the system was removed from service to support required surveillance testing. At approximately 1450 hours0.0168 days <br />0.403 hours <br />0.0024 weeks <br />5.51725e-4 months <br />, during the performance of the surveillance test, it was discovered that the high hydrogen level annunciator and associated alarm lamp did not operate when required during testing.
The redundant Channel #11 was verified to be operable prior to removal of Channel #12 from service.
Cause of Event During performance of Channel #12 CHM System functional test, the high hydrogen level annunciator failed to alarm in the control room as expected. The associated main system control hydrogen alarm lamp also failed to illuminate as expected. The cause was determined to be a failed time delay relay.
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-a NMP1L 1879 Page 2 Corrective Actions The relay was replaced and post maintenance testing was completed satisfactorily.
Channel #12 of the CHM System was declared operable on October 13, 2004, at approximately 1300 hours0.015 days <br />0.361 hours <br />0.00215 weeks <br />4.9465e-4 months <br />.
TJO/RF/jrm cc:
Mr. S. J. Collins, NRC Regional Administrator, Region I Mr. G. K. Hunegs, NRC Senior Resident Inspector