ML19294B430
| ML19294B430 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, LaSalle  |
| Issue date: | 02/11/1980 |
| From: | Peoples D COMMONWEALTH EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| IEB-79-28, NUDOCS 8002280352 | |
| Download: ML19294B430 (2) | |
Text
-
Commonwealth Edison 3b one First National Plata. Chicago, liknots Address Reply to: Post Office Box 767 Chicago, tilinois 60690 February 11, 1980 Mr. James G. Keppler, Director Directorate of Inspection and Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137
Subject:
LaSalle County Station Units 1 and 2 Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 Response to IE Bulletin No. 79-28 NRC Docket Nos. 50-373/374/454/455/456/457
Reference:
(a)
J. G. Leppler letter to C. Reed dated December 10, 1979
Dear Mr. Keppler:
Reference (a) transmitted I.E. Bulletin 79--28 which requested a response within sixty days concerning the use of NAMCO model EA 180 limit saitches of Byron, Praidwood, and LaSalle County Stations.
A review of the mechanical drawings has identified NAMCO EA180 limit switches on safety-related equipment at Byron and Braidwood Stations.
The electrical installation colitractors at these stations have been requested to locate and replace the cover gaskets on NAMCO EA160 switches encoded with dates 02-79 through 08-79 that are in the Containment Building and in stock.
The electrical contractors have also been requested to submit to the Station Construction Departments written procedures for performing and documenting the cover gasket replacement.
The replacement program will be limited to the Containment Building (and stock) because we do not feel that it is necessary to replace the cover gaskets on all of the suspect switches; only those that might be exposed to a continuous ambient teaperature of greater than 1750F.
NAMCO has stated (Reference (a)) that the potential problem with the cover gaskets on the EA180 switches occurs only when the gaskets are subjected to continuous ambient service conditions of greater than 1750F.
Their letter states that no 80022sa B S E FEB 121980
/
Commonwealth Edison Mr. J. G. Keppler NRC Docket Nos.
February 11, 1980 50-373/374/454/455/456/457 Page 2
corrective action is necessary for those switches that are not sub}ectedtoacontinuousambienttemperatureofgreaterthan 175.
Based on the design ambient conditions of the plant, the only location where ambient temperatures might exceed 1750F for extended periods of time is inside the Containment Building.
Therefore, it is only necessary to replace the gaskets on EA180 switches inside the Containment Building.
Gaskets will be replaced on all suspect switches in stock, to prevent possible future problems if they are used inside the Containment Building.
We expect that the fdentification and replacement of cover gaskets on limit switches with the suspect date codes will be completed by May 31, 1980.
Although incomplete, inspections and review of drawings at LaSalle County Station have not identified the use of any NAMCO model EA 180 limit switches to date.
This review is expected to be complete in approximately one month.
Please address any questions you may have concerning this matter to this office.
Very truly yours, sk.
Qy q
D.
L. Deoples Director of Nuclear Licensing cc:
Director, Division of Reactor Operations Inspection