05000219/LER-1982-039, Forwards Updated LER 82-039/03X-1.Detailed Event Analysis Encl

Forwards Updated LER 82-039/03X-1.Detailed Event Analysis Encl

ML20063N222
Person / Time
Site:	Oyster Creek
Issue date:	09/10/1982
From:	Fiedler P GENERAL PUBLIC UTILITIES CORP.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20063N224	List: 05000219/LER-1982-039, Forwards Updated LER 82-039/03X-1.Detailed Event Analysis Encl
References
NUDOCS 8209200104
Download: ML20063N222 (3)

LER-2082-039, Forwards Updated LER 82-039/03X-1.Detailed Event Analysis Encl

Event date:
Report date:
2192082039R00 - NRC Website

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GPU Nuclear

'. gg g{ P.O. Box 388 Forked River, New Jersey 08731 609-693-6000 Writer's Direct Dial Number:

Septenber 10, 1982 Mr. Ronald C. Haynes, Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Dear Mr. Haynes:

Subj ect: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Zeport Update Reportable Occurrence No. 50-219/82-39/03X-1 Tt.is letter forwards three copies of a Licensee Event Report Update to report Reportable Occurrence No. 50-219/82-39/03X-1 in compliance with paragraph 6.9 2.b.2 of the Technical Specifications.

Very truly yours,

,b ,- - _ --J 2 Pet 6r B. Fiedler Vice President and Director Oyster Creek PBF:lse Enclosures cc: Director (40 copies)

Office of Inspection and Enforcement U.3. Nuclear Regulatory Commission Washington, D.C. 20555 Director (3)

Of fice of Management Information and Program Control U.S. Nuclear Regulatory Commission Washington, D.C. 20555 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731 8209200104 820910 PDR ADOCK 05000219 s PDR GPU Nuclear is a part of the General Pubhc Utihties System g6 0 j

OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Update Reportable Ocytrrence No. 50-219/82-39/03X-1 Report Date September 10, 1982 Occurrence Date July 1, 1982 Identification of Occurrence During surveillance testing, the backup valve monitoring channel (thermocouple) for Safety Valve NR28J was found to be inoperable. This condition is permitted by a limiting condition for operation as given in paragraph 313.B.2 of the Technical Specifications.

This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6 9 2.b.2.

Conditions Prior to Occurrence The plant was in steady state of operation.

Major Plant Parameters:

Power: Reactor - 1521 MWt Generator - 505 MWe Mode Switch Position: RUN Description of Occurrence During the performance of the " Thermocouple Valve Monitoring System Monthly Channel Check" procedure, the thermocouple for Safety Valve NR28J was found to be inoperable (not meeting procedural acceptance criteria).

In accordance with Section 3 13.B.2 of the Technical Specifications, the acoustic monitors (primary indication) for safety valves NR28J, NR28H and NR28K were checked. Since the acoustic monitors for all three valves were operable, the limiting condition for operation was met by reducing the setpoint of the acoustic monitor on one of the adjacent valves (NR28H).

Apparent Cause of Occurrence The cause of the thermocouple failure was due to one terminal screw inside primary containment backing out, causing the terminal to make intermittent contact, thus resulting in erratic readings.

Licensee Event Report Update Page 2 Reportable Occurrence No. 50-219/82-39/03x-1 Analysis of Occurrence There are two types of instruments installed on the safety and relief valves in order to detect inadvertant valve opening. The primary indication is an acoustic monitor which senses acoustic levels at the valve discharge. The backup indication is a thermocouple which senses the temperature at the valve discharge. Per Technical Specifications, the adjacent safety valves must have operable acoustic monitors, if a cafety valve thennocouple is declared inoperable. In this case, the setpoint of one of the adjacent acoustic monitors is reduced, due to the fact that the valves are physically close together so that the acoustic monitor for the adjacent valve detects the opening of the valve next to it. Since the acoustic monitor for the affected safety valve was operable, appropriate actions were taken per Technical Specifications, and as the thermocouple serves as a backup indication for the acoustic monitor, the safety significance of this event is considered minimal.

Corrective Action The immediate corrective action taken was to reduce the setpoint of an adjacent safety valve's acoustic monitor.

During a recent outage, the subject terminal screw was replaced, tightened, and placed back in service. The setpoint of the adjacent safety valve's acoustic monitor was increased to its original setting.

Failure Data This thermocouple previously failed and was replaced during an outage on May 25, 1982.

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