ML19256F179
| ML19256F179 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 10/29/1979 |
| From: | William Cahill CONSOLIDATED EDISON CO. OF NEW YORK, INC. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| IEB-79-24, NUDOCS 7911210579 | |
| Download: ML19256F179 (2) | |
Text
71 William J. Cahill, Jr.
v.ce Procert Ccnschasted Ed son Cer pany of New York. Inc.
4 Irwng Place. New York. N Y 10003 Telecrone (212) 460 3819 October 29, 1979 Indian Point Station Docket No.50-003 50-247 Mr. Boyce H. Grier, Director Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission, Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 Dear Mr. Grier The following is in response to the concerns raised by IE Bulletin No. 79-24:
The electrical heat tracing system for Unit #2 is com-prised of three separate subsystems.
The subsystem for freeze protection is supplied by two control cabinets -
one located in the nuclear tank farm area and theother in the intake structure area.
These cabinets supply individual heat tracing circuits, arranged in parallel and supplied by a single main contactor, which is con-trolled by ambient temperature.
The safety related process, instrument and sampling lines containing liquids which could be adversely affect-ed by subfreezing temperatures have been provided with electrical heat tracing which is controlled from the aforementioned control cabinets.
This heat tracing in conjunction with insulation has been designed to maintain piping contents within a temperature range of 35cF to 45cF, when continuously and simultaneously subjected to an ambient air temperature of minus SoF and a wind velocity of 40 mph while the contents of the pipe are in a static condition.
In addition, associated instruments exposed to the outside environment are mounted in weather proof boxes provided with electric strip heaters.
13//
314 791121 02577
, To insure that our freeze protection is currently adequate, a physical inspection was conducted on all safety related process, instrument, and sampling lines which could be exposed to sub-freezing temperatures.
As a result of this inspection it has been determined that adequate protection measures are present to assure that safety-related process, instrument, and sampling lines will not freeze during extreme cold weather.
Very truly yours f
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CC:
Mr. T. Rebelowski, Resident Inspector U.
S. Nuclear Regulatory Commission P. O. Box 38 Buchanan, New York 10511 13//
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