ML20140G318
| ML20140G318 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 06/18/1985 |
| From: | Dixon O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| SPR-85-005, SPR-85-5, NUDOCS 8507120610 | |
| Download: ML20140G318 (2) | |
Text
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S SOUTH CAROLINA ELECTRIC & GAS COMPANY Post orrice 7e4 CptuotA. south CAnoWNA 29218 M ri } ** D D r
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'dh June 18, 1985 Dr.
J.
Nelson Grace Regional Administrator U.S.
Nuclear Regulatory Commission Suite 2900 101 Mariett'a Street, NW Atlanta, Georgia 30323
SUBJECT:
Virgil C. Summer Nuclear Station Docket No. 50/395 Operating License No. N P F-12 Special Report (SPR 85-005)
Dear Dr. Grace:
Attached is a Special Report for the Virgil C.
Summer Nuclear Station.
This Special Report is required by Section 6 of the Technical Specifications.
Sh ou ld there be any questions, please call us at your convenience.
r-ery t u y yours,
\\
hbW+vs hN 1 on, Jr.
RMF:0WD/csw Attachment cc:
V.
C.
Summer K.
E.
Nodland T.
C.
Nichols, Jr./O.
W.
Dixon, Jr.
R.
A.
Stough E.
H.
Crews, Jr.
G.
Pe r c iv a l E.
C.
Roberts C.
W.
Hehl W.
A.
Williams, Jr.
J.
B.
Knotts, Jr.
D.
A.
Nauman S.
D.
Hogge Group Managers I&E Washington O.
S.
Bradham Document Man age men t C.
A.
Price Branch S.
R.
Hunt INPO Records Center J.
F.
Heilman ANI Lib r a ry C.
L. Ligon (NSRC)
NPCF File
-[g 7,Te 8507120610 850618 PDR ADOCK 05000395
/
S PDR L
O Dr.
J.
Nelson Grace SPR 85-005 June 18, 1985 EVENT DESCRIPTION On May 17, 1985 the Licensee's Appendix R Task Force id en t i f ie d that separation of the Nuclear Instrument (NI) Source Range (SR) Detectors (N-31, N-32, and N-33) did not meet the requirements of 10 CFR 50 Appendix R.
The "B"
train power supply for NI SR channel N-33 shares a common breaker with a 7200 volt cable which runs in the same fire. area ("B" train cable chase, Room 36-03CB) as the "A"
train s ignal cab les for NI SR channel N-31 and N-32.
A fire in this area c ou ld damage channel N-31 and N-32 and als o dis rupt power to N-33.
These circuts are separated by a horizontal dis tance of greater than twenty feet; however, because of intervening c omb u s t ib l e s,
i.e, insulation of electrical cables, the requirements of Appendix R are not satisfied.
There were no adverse consequences due to this event.
Detector N-33 is the SR indicator located on the Control Room Evacuation Panel (CREP).
A fire in the "B"
train c ab le chase wou ld not require a Control Room evacuation or the use of the CREP.
Shutdown wou ld be accomplished from the Control Room using "A" train equipment.
CORRECTIVE ACTION The Licensee e s t ab lis hed a one hour fire watch patrol o f the area as required by Technical ' Specification 3.7.10, " Fire Rated As s emb li e s. "
A modification to the existing installation of NI-33 is presently being processed wh ic h will provide isolation of NI-33 from.NI-31 and NI-32.
This modification will be implemented no later than March 31, 1986.
L