ML20207S804
| ML20207S804 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 03/16/1987 |
| From: | Gucwa L GEORGIA POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| SL-1944, NUDOCS 8703200283 | |
| Download: ML20207S804 (2) | |
Text
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Georgia Fowir Company o
- 333 Piedmont Avenue Atlanta, Georgia 30308
' Talephone 404 526-6526 Maihng Address:
Fost Office Bcx 4545 Atlanta, Georgia 30302 h
Georgia Power L T. Gucwa tt e scuttwn electnc system Manager Nuclear Safety and Licensing gg 0076U March 16, 1987 Secretary of the Commission U. S. Nuclear Regulatory Commission Attn: Documeat Control Desk Washington, D.C.
20555 NRC DOCKETS 50-321, 50-366 OPERATING LICENSES DPR-57, NPF-5 EDWIN I. HATCH NUCLEAR PLANT UNITS 1, 2 ENVIRONMENTAL QUALIFICATION OF ELECTRICAL PENEU ATIONS Gentlemen:
Georgia Power Company (GPC) recently received a copy of the viewgraphs used by the Nuclear Regulatory Commission (NRC) staff in a presentation at the December 8, 1986 Operating Reactor Events meeting.
One of the viewgraphs relating generally to the nylon cable splice issue indicated that both units of Plant Hatch contained a limited number of the splices in question and that they were unqualified.
It further indicated that a justification for continued operation (JCO) had been prepared for each unit. We wish to clarify and expand the information in the viewgraphs.
First, GPC determined on or before December 6, 1986 that no unqualified nylon splices for GE containment electrical penetrations are present in Unit l
2.
GPC, however, concluded that the possibility existed that nylon cable j
splices, of the type in question, might be present in the Unit 1 flSIV limit i
switch circuits.
A JC0 was prepared for Unit 1 due to this possibility and l
limited available information associated with the actual failures of the splices tested at Wyle Laboratories.
By December 18, 1986, our engineering support had determined that the splices on the MSIV limit switch circuits at Hatch Unit 1 were environmentally qualified, even assuming that the splices were identical to those tested at Wyle Laboratories.
This conclusion was based on the operational requirements of the affected cable and limit switches.
The limit switch circuits operate on 120 VAC, initiate reactor trip on closure of MSIVs, and would only be required to be functional to assure safe shutdown conditions for the first few seconds after a postulated event.
The Wyle Laboratores tests did not invalidate the nylon splices tested when used in this voltage range and over such a limited time period.
The potential temperature and radiation effects induced on the splices during the time the limit switches are required to be operational are minimal, and therefore they can be considered to be environmentally qualified under 10 CFR 50.49.
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U. S. Nuclear Regulatory Commission SL-1944 ATTN: Document Control Desk 0076U
-March 16, 1987 Page Two Should questions or a need for additional information arise, please contact me.
Sincerely, 47 4 - = ~
L. T. Gucwa KWWhitt/jhu c: Georgia Power Company Mr. J. P. O'Reilly Mr. P.
R.' Bemis Mr. R. D. Baker Mr. D. M. Crowe G0-NORMS Southern Company Services Mr. L. B. Long Mr. C. R. Pierce NUCLEAR REGULATORY COMMISSION Dr. J. N. Grace, Regional Administrator Mr. G. W. Rivenbark, Licensing Project Manager