ML20084E245
| ML20084E245 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 05/26/1995 |
| From: | Ray D COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9506010354 | |
| Download: ML20084E245 (1) | |
Text
Cnmmonwealth filiw>n Company
.qp laNalle Generating $tation
/
2601 North 21st 1(nad Marwilles, 11.61361-9757 Tel HI 43574761 May 26,1995 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D. C. 20555 This special report is submitted in accordance with LaSalle Unit 1 Operating Ucense NPF-11, Appendix A, and Technical Specifications 3.3.7.12 and 6.6.c, regarding a Unit 1 Loose Pans Monitor System Test Failure.
Technical Specification 3.3.7.12 requires that a special report be written within 10 days after one or more loose parts channels are Inoperable for more than 30 days.
On April 20,1995, with LaSalle Unit 1 at 100% power, the Loose Parts Monitor (LPM) system channel 10 was declared inoperable due to a low audio signal. This condition could possibly prevent the channel from producing an alarm.
The apparent cause of the channel degradation is unknown at this time. Testing has determined that the problem is inside the primary containment.
At the time of the event, the LPM System was required for Unit 1, but one inoperable channel does not prevent the system from performing its design function. Channels 7,8,9, and 10 are the sensors on the upper section or ring of the reactor vessel. Channels 7,8, and 9 provide sufficient redundancy % detect a loose part if it occurred near Channel 10.
The defective channel 10 will not be repaired until the next forced or scheduled outage due to limited accessibility of the channel components during unit operation.
Sincerely, hth n
eSo 88'
.J. Ray gg Station Manager oo LaSalle County Station b*
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NRC Region lil Administrator y
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