ML20127H647

PNO-TMI-85-004:on 850515,upper Plenum Assembly Removed from TMI-2 Reactor Vessel & Placed in Storage.Removal Will Permit Unobstructed Access to Core Region for Defueling.Defueling Scheduled to Commence in Sept 1985

ML20127H647
Person / Time
Site:	Three Mile Island
Issue date:	05/15/1985
From:	Cowgill C, Moslak T, Travers W Office of Nuclear Reactor Regulation
To:
References
PNO-TMI-85-004, PNO-TMI-85-4, NUDOCS 8505210347
Download: ML20127H647 (1)

Text

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n 50320-850515 May 15, 1985 NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE-PNO-TMI-85-04 This preliminary notification constitutes EARLY notice of events cf POSSIBLE safety or public interest significance. The information is as initially received without verifi-cation or evaluation and is basically all that is known by NRC staff on this date.

Facility: GPU Nuclear Corporation Licensee Emergency Classification:

Three Mile Island, Unit 2 X Not Applicable

. Docket Number 50-320

Subject:

PLENUM ASSEMBLY REMOVAL On Wednesday, May 15, 1985, the upper plenum assembly was removed from the THI-2 reactor vessel and placed in storage under water in the deep end of the refueling transfer canal. All equipment performed satisfactorily during the transfer. The radiation exposure rates for the removal and transfer were below those estimated and worker doses were less than anticipated. No offsite release was observed during the plenum transfer.

The plenum assembly is an approximately 12 foot by 12 foot cylinder weighing about 55 tons that ' serves as a support structure for control rod guide tubes and as a reactor coolant flow distributor.

Prior to removing the plenum, potential interference points were inspected and cleaned and unsupported fuel assembly end fittings were dislodged. After completion, the plenum assembly was raised 7&" using hydraulic jacks to ensure a controlled lift.

Jacking was completed in December 1984.

Removal of the plenum assembly will permit unobstructed access to the core region for defueling. .Defueling is scheduled to commence in September 1985.

M:dia interest may occur because of public sensitivity to TMI related events. The Commonwealth of Pennsylvania was informed.

This information is current as of 2:45 PM, May 15, 1985.

This preliminary notification is issued for information only and the NRC plans to continue monitoring events as they occur.

Contact:

T. Mosla 0-1128 C. Cowgill 590-11 W. T avers 590-1120 Distributign:

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CA J. Tourtellotte PDR D0T:(Trans. Only) kR $47850515 PNO-THI-85-oo4 PDR

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