ML19282B700
| ML19282B700 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 02/02/1979 |
| From: | Ross D JERSEY CENTRAL POWER & LIGHT CO. |
| To: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| NUDOCS 7903160135 | |
| Download: ML19282B700 (2) | |
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Jersey Central Power & Light Company
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Madison Avenue at Punch Bowl Road Morristown. New Jersey 07960 (201)455-8200 February 2, 1979 Mr. Boyce H. Grier, Director Office of Inspection and Enforcement United States Nuclear Regulatory Commission Region 1 631 Park Avenue King of Prussia, Pennsylvania 19406
Dear Mr. Grier:
Subject:
Oyster Creek Nuclear Generating Station Docket No. 50-219 I E Bulletin No. 78-14 The purpose of this letter is to respond to the directives set forth in I E Bulletin No. 78-14 which is concerned with the deterioration of Bula-N components in ASCO solenoid valves in BWR control rod scram T systems. A review has been completed of all Buna-N material applications in the core assemblies, diaphrams and associated parts in the hydraulic control units of the control rod drive system at Oyster Creek.
It has been determined that except for the replacements made during the most recent refueling outage (September - December 1978) the Buna-N material in all CRD scram pilot valves, backup scram valves, scram discharge volume vent and drain pilot valves, and scram discharge volume test valves must be considered to have been in service since the plant went operational.
During the 1978 outage, seventeen (17) hydraulic control units in a checkerboard pattern were chosen for ASCO scram valve parts replace-ment in accordance with General Electric SIL No. 128 and a special General Electric inspection program. No cracking of the Buna-N material was discovered although some of the components were found to have experienced some shrinkage and others had hardened slightly due to natural aging.
After reviewing the condition of the Buna-N material at Oyster Creek, GE recommended that the remaining core discs be replaced on a routine basis during future outages.
In response to a subsequent inquiry by the plant staff, GE confirmed their position that there is no immediate need to replace the Buna-N material.
Based on the GE data and information, a schedule is presently being developed to inspect and replace the Buna-N material in the remaining valves during the next three (3) years.
Should future tests or inspections indicate the need, complete replacement will be accomplished in a shorter time frame.
The valves overhauled in any one outage will be associated with control rod drives selected from a distributed 7 9 0 316 01M Q
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Jersey Central Power & Ught Company is a Member of the General Pub 0c UtSt:es System
h!r. Boyce II. Grier, Director February 2, 1979 I
checkerboard pattern as outlined in General Electric SIL No. 128, Revision 1, Supplement 1.
In addition, the plant's preventive maintenance program will be expanded to include the inspection and replacement of the Buna-N material in each valve on a periodic basis to assure that the componente are not used in excess of (7) years.
V truly yours, s
D. A. Ross, Manager Nuclear Generating Stations mmm cc:
United States Nuclear Regulatory Commission Office of Inspection and Enforcement Division of Reactor Operations Inspection Washington, D. C.
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