ML20132B472
| ML20132B472 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 09/12/1985 |
| From: | Dixon O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-85-425-000 PT21-85-425, PT21-85-425-000, SPR-85-011, SPR-85-11, NUDOCS 8509260200 | |
| Download: ML20132B472 (2) | |
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SOUTH CAROLINA ELECTRIC & GAS COMPANY rosT oppica 7s4 Cou;usiA. SouYH CAROLINA 29218 P5' SEP 17 All. I 4 O. W. OlxoN, Jm.
Viet PRESIDENT J
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September 12, 1985 Dr. J. Nelson Grace Regional Administrator U.S. Nuclear Regulatory Commission Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323
SUBJECT:
Virgil C. Summer Nuclear Station Docket No. 50/395 Operating License No. NPF-12 Special Report (SPR 85-011)
Dear Dr. Grace:
Please find attached a fourteen (14) day Special Report for the Virgil C. Summer Nuclear Station.
This report is submitted pursuant.to the requirements of Technical Specification 6.9.2 as a result of entry into Action Statement 30 of Technical Specification 3.3.3.1, " Radiation Monitoring Instrumentation," on August 29, 1985.
Should there be any questions, please call.us at your convenience.
Ver truly yours
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.c f O. W. Dixon, y
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CJM:OWD/ led Attachment cc:
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C. Summer K.
E.
Nodland J. A. Warren R.
A. Stough T. C. Nichols, Jr./0. W. Dixon, Jr.
G.
Percival-E. H.
Crews, Jr.
C. W. Hehl E. C. Roberts
'J.
B.
Knotts, Jr.
W. A. Williams, Jr.
S. D. Hogge D. A. Nauman I&E Washington Group Managers Document Management O. S. Bradham Branch C. A. Price INPO Records Center S. R. Hunt ANI Library J. F. Heilman NPCF C. L. Ligon (NSRC)
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8509260200 850912 PDR ADOCK 05000395,,
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r Dr. J. Nelson Grace SPR 85-011 Page Two September 12, 1985 EVENT DESCRIPTION AND ACTION TAKEN On August 29, 1985 with the plant in Mode 1, Radiation Monitor RM-A14, " Reactor Building Purge Exhaust and Supply System Monitor," was declared inoperable due to spurious alarms and indications.
The preplanned alternate method of monitoring was subsequently established in accordance with Action Statement 30 of
~ Technical Specification 3. 3. 3.1.
Maintenance personnel investigating the event'were unable to' identify the specific cause of the spurious indications previously observed by Operations.
All indications were observed to be normal during the troubleshooting of the monitor.
As a preventative measure, all connections were cleaned prior to the performance of a channel calibration and operational test.
RM-A14 was declared operable on September 4, 1985, on completion of the surveillances.
On September 7, 1985, RM-A14 again experienced spurious indications as previously noted in this report.
The monitor was declared inoperable and plans established to implement the alternate method of monitoring if repairs could not be completed within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
On September 10, 1985, the component causing the spurious-indications was determined to be the Low Range Amplifier Circuit Board.
The board was replaced and RM-A14 returned to operable status.
CAUSE OF THE INOPERABILITY The cause of the intermittent problem appears to be an electronic component breakdown on the monitor's low range amplifier circuit board.
PLANS FOR RESTORING TO OPERABLE STATUS The monitor was returned to operable status after the completion of a satisfactory channel calibration at 1440 hours0.0167 days <br />0.4 hours <br />0.00238 weeks <br />5.4792e-4 months <br /> on September 10, 1985.
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