ML19319E413
| ML19319E413 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 11/07/1975 |
| From: | ARKANSAS POWER & LIGHT CO. |
| To: | |
| Shared Package | |
| ML19319E405 | List: |
| References | |
| NUDOCS 8004100695 | |
| Download: ML19319E413 (3) | |
Text
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Unusual Event Report No. 50-313/75-3 2.
Report unte:
11/7/75 3.' Occurrence Date:
10/9/75 4
Facility:
Arkansas Nuclear One-Unit.1 F.ssellvi11e,' Arkansas 5.
Identification of Occurrence':
Strong motion accelerographs were not mounted correctly.
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Conditions Prior to Occurrence:
Steady-State Power X
Reactor Power 2504 blNth llot Standby Not Outpu:
800 stwe Cold Shutdown hicent of Full Power 97.5 %
i Refueling Shutdown Load Chr.nges During Routine Power Operation
- C Routine Startup Operation Routine Shutdown Operation-Other (specify) f i
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Description of Occurrence:
4 The Strong blotion Accelerograph located on top of the reactor building at elevation 531'-6" and on the base slab at elevation 335'-0" were not mounted correctly. They were found setting in their proper location but not belted to the base slab or the reactor building as requirc.i by FSAR Section 2.7.6.
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Designation of Apparent Cause of Occurrence:
Design Procedure-Manufacture Unusual Service Condition Including linvironmental Installation /
X' Construction Component Failure Operator Other (specify)
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Analysis of Occurrence:
The apparent cause is the failure of Bechtel Construction to mount the Strong Motion Accelerographs as required by the. FSAR and vendor instru-ctions. The alarm mechanisms, which are separate units, were mounted correctly and would have provided the control room information necessary in the event of a seismic occurrence. No seismic occurrences have been alarmed and periodic testing has proven the operability of the alarms.
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. Unusual Event _ Report No.- 50-313/75-3 10.
Corrective Action:
- The Strong Moti'on Accelerographs were mounted correctly on October 18f 1975.
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Failuro Data:
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