ML20008G194
| ML20008G194 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 06/23/1981 |
| From: | Nichols T SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| REF-PT21-81-451-000 10CFR-050.55E, 10CFR-50.55E, PT21-81-451, PT21-81-451-000, NUDOCS 8107020424 | |
| Download: ML20008G194 (2) | |
Text
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SOUTH CAROLINA ELECTRIC a GAS COMPANY mo st OF'sC E so n,e*
COLUMBIA. COUTH CAROUNA 29218 I
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'1 T. C. Nicuo Ls, J n.
June 23,1981 j
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Mr. James P. O'Reilly, Director Q
L U. S. Nuclear Regulatory Commission 7
Jul 0 y ggM P t'
, '.n Region II, Suite 3100
-3 p'. v.s. % ssp 4 101 Marietta Street, N.W.
Atlanta, Georg,ia 30303 SubjecN(%g fV ummer Nuclear Station
.o. 50/395 gj - 39{
Substantial Safety Hazard Volume Control Tank Nuclear Eng.
File 3.1051
Dear Mr. O'Reilly:
On June 15, 1981, Mr. Virgil Brownlee of NRC Region II was notified of substantial safety hazard under 10CFR21 concerning the Volume Control Tank Level Control System. This item was first reported to Mr. Virgil Brownlee on June 4, 1981 as a potential significant deficiency or potential substantial safety hazard.
This item is being reported under SCE&G's 10CFR 50.55e procedure.
The information shown on the attachment to this letter serves as the interim 30 day report.
The final report will be written when the corrective action is determined.
If you have any questions, please advise.
Very uuly yours, e
A T. C. Nichols, Jr.
JG:TCN:lkb cc:
V. C. Summer M. N. Browne G. H. Fischer H. E. Yocom H. N. Cyrus B. A.'Bursey T. C. Nichols, Jr.
J. K. Skolds
- 0. W. Dixon, Jr.
@ (Washington)
D. A. Nauman Document Management Branch W. A. Williams, Jr.
.(55e, 21, LER only)
R. B. Clary NPCF
- 0. S. Bradham File A. R. Koon A. A. Smith f8 i
H. Radin Dr. J. Ruoff
'81070 20 %2f 3
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10CFR21 - SUBSTANTIAL SAFETY HAZARD 1.
Name and Address of Reporting Individual John M. Gesn South Carolina Electric and Gas Company 320 South Main Street Columbia, SC 29218 2.
Identification of Basic Component Volume Control Tank Level Control System I
3.
Identification of Firm Supplying Component Westinghouse Electric Corporation Water Reactors Division 4.
Nature of Defect, Substantial Safety Hazard Created, and Evaluation With the reactor plant operating with a centrifugal charging pump, a single failure of the volume control tack level control system (LT115 failed high) would cause letdown flow to be diverted to the liquid holdup tank.
The VCT level decreases due to normal charging. Automatic makeup at 20% level i
would not occur due to the failed LT115 transmitter. Additionally, emergency makeup would not start at 5% level because it takes a 5% level signal from both LT112 and LT115 to initiate this. Without operator intervention the VCT could empty causing the operating charging pump to be damaged due to loss of suction. Elf it is assumed that one charging pump is out of service as allowed by technical specifications then only one charging would be available to provide makeup to the reactor coolant system. The one remaining pump does not meet the single failure criteria.
5.
Date Information of Defect was Obtained May 22, 1981 l
6.
Number and Location of Defect l
Volume Control Tank level control system - LT115 7.
Corrective Action l
l The corrective action will be supplied in the final report.
8.
Advice to Purchasers or Licensees None.
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