ML20057C748

Informs That Util Will Make Reactor Vessel Water Level Instrumentation Mod During Planned Outage Scheduled to Begin in Sept 1994,in Accordance W/Gl 92-04 & Requests NRC Concurrence

ML20057C748
Person / Time
Site:	Oyster Creek
Issue date:	09/22/1993
From:	Long R GENERAL PUBLIC UTILITIES CORP.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
C-93-2209, C000-93-2209, C321-93-2257, GL-92-04, GL-92-4, NUDOCS 9309290339
Download: ML20057C748 (2)

Text

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1 GPU Nuclear Corporation l M Mp er One Upper Pond Road d w EME Parsippany, New Jersey 07054 201-316-7000 l TELEX 136-482 Writers Direct Dial Number.

September 22, 1993 C000-93-2209  !

C321-93-2257 U. S. Nuclear Regulatory Commission Att: Document Control Desk Washington, DC 20555

Subject:

Oyster Creek Nuclear Generating Station (OCNGS)  !

Docket No. 50-219 ,

Reactor Vessel Water Level Instrumentation ,

During the past two weeks there have been numerous communications between the NRC staff and GPU Nuclear regarding reactor vessel level instrumentation. GPU Nuclear's commitment, as included in the Integrated Schedule Plan, is to modify the condensing chamber during the 15R outage, which is currently scheduled to begir. in September 1994. In a letter dated September 20, 1993 i NRC has requu.ted GPU Nuclear modify the reactor vessel water level 1 instrumentation during the next cold shutdown after October 1,1993. GPU Nuclear herein modifies its commitment in order to meet NRC concerns.

GPU Nuclear's proposed modification as referenced in NRC's September 20, 1993 letter will eliminate the counterflow of steam and condensate, thereby eliminating the concentrating mechanism and thus the root cause of the noncondensible gas problem in the reactor vessel level instrumentation. This passive modification is in the design phase and has not yet been fabricated.

As discussed above, the GPU Nuclear modification has been included in our >

Integrated Scheduling Plan to support an implementation schedule in accordance s with Generic Letter 92-04. The GPU Nuclear schedule currently shows a preparation for modification installation of April 15, 1994.

Based on preliminary planning, the length of a cold shutdown of s.ufficient  !

duration to install this modification, would be approximately 14 days. Our J estimate is aggressive in that all. work must be performed inside the drywell l (containment). Access must follow cooldown and de-inerting of the drywell. ,

Working conditions within the drywell are harsh, therefore, productivity.will  !

be reduced. The erection and removal of scaffolding, a pre-walkdown prior to I installation, preparation for a freeze seal and welding cannot be pre-staged.

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ppg g GPU Nucl ear Corporation is a subsidiary of General Pubhc Utikties Corporation j i

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J000-93-2209 C321-93-2257 Page 2

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A In order to meet NRC concerns, steps will be taken to accelerate the readiness of the modification or installation. GPU Nuclear commits to install the proposed modification during any unplanned cold shutdown after January 7, 1994 with an anticipated duratica which exceeds the minimum estimated installation time of 14 days.

In any event, GPU Nuclear will make the modification during its planned outage scheduled to begin in September 1994 and requests NRC's concurrence with the above. If further discussion or clarification is warranted, please call me at (201) 316-7484.

Sincerely,

/ b # -f w b Robert L. Long /'

Vice President and Director, Services Division Enclosures MWL/plp cc: Administrator, Region I Senior Resident Inspector '

l NRC OCNGS Project Manager ,

James G. Partlow - Associate Director for Projects 1 Steven A. Varga - Director, Division of Reactor Projects 1/II l

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