ML20214G490

Transfer of Lead Responsibility IE-C&O-75-6 Re Possible Design Changes in Mark II Containments at Limerick & Susquehanna for Loads & Effects Produced During Safety/ Relief Valve & LOCA blow-down Discharges Into Suppression

ML20214G490
Person / Time
Site:	Susquehanna, Limerick, 05000000
Issue date:	04/23/1975
From:	Deyoung R, Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE), Office of Nuclear Reactor Regulation
To:	Deyoung R Office of Nuclear Reactor Regulation
Shared Package
ML20214G486	List: ML20214G482 ML20214G490
References
CON-WNP-0012, CON-WNP-12 IE-C&O-75-6, NUDOCS 8605220223
Download: ML20214G490 (2)

Text

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G C Date: APR 2 3 1975 Serial flo.,: IE-C&O-75-6 TRANSFER OF LEAD RESPONSIBILITY To: R. C. DeYoung, Assistant Director for Light Water Reactors, Group 1, RL Subject _: POSSIBLE DESIGN CHANGES IN THE MARK II CONTAINMENTS AT THE LIMERICK AND THE SUSQUEHANNA FACILITIES - DOCKET

,, Nos. 50-352/353 AND 50-387/388 Responsible Branch Chief: K. V. Seyfrit Description of Item' Requiring' Resolution:

The two licensees of these facilities have notified IE, in writing, of possibic design changes to be made in order to accommodate the loads and effects produced during safety / relief valve and LOCA blow-down discharges into the suppression pool. The phenomena associated with these events have been under study by General' Electric as part of the testing program to validate the Mark III contaipment concept.

The specific areas of concern are the potential increased loads on the structures and equipment located above the water level in the suppression pool, the loads on the vertical vent pipes, the loads on the pool boundaries and the loads on the submerged components.

The licensee for the Susquehanna facility has suspended all concrete placement and other critical activities related to the containment until any necessary design changes have been identified. The licensee for the Limerick facility is reviewing the uncompleted portions of the containment and internal structures associated with these phenomena-and will delay work if its completion would preclude implementation of any necessary modifications.

Recomendations and Proposed Course of Action:

1. NRR will, through the Licensing Project Managers, and the technical support of the Division of Technical Review', obtain the infonnation from General Electric which describes the phenomena involved and the resulting conditions which will be imposed on the structures, systens and components responding to the events.

2. NRR will obtain information from these licensees regarding any necessary design changes resulting from the definition of any 8605220223 760416 PDR ADOCK 050003S2 A PDR

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/ . hPR 23 1975 Tran: fer of Lead Responsibility .

new design conditions imposed by General Electric. In additio'n, fiRR will complete this action for the remaining licensees who are utilizing the BWR Mark 11 Containment.

3. fiRR will review and evaluate the necessary design changes and the method of integrating them into the currently approved designs and the currently partially constructed portions of the containments and internal structures. In addition, fiRR will complete this action for the remaining licensees who are utilizing the BWR Mark II Containment.

4. IE will verify adherence to any modifications imposed by f4R3 in the requirements for the construction'of these facilities and'others identified by fiRR.

References:

1. Letter from Robert T. Carlson, Chief, FC&ES Branch, IE:I to H. 'D.- Thornburg, Chief FS&E Branch, IE:HQ, dated April 1,1975.

2. Letter from N. W. Curtis, Vice President - Engineering and

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Construction, Pennsylvania Power & Light Company to James P.

O'Reilly, Director, IE:I, dated April 4, 1975 reporting information in accordance with 10 CFR 50.55(e).

3. Letter from V. S. Boyer, Vice President, Phil:.delphia Electric Company to Donald F. Knuth, Director,.IE, dated April 4,.1975 reportinginformationinaccordancewith10CFR50.55(e).

Concurra c,e:

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h. HI Grief, Assistant Director for Construction & Operations, IE j0 ate .

l At $'Date

$75 R."C. DeYoulng, pnristant p rector for Light Water Reactors, Group 1. RL g, ' [

cc: D. F. Knuth, IE II. D. Thornburg, IE A. Giambusso, RL J. P. 0' Reilly, IE:I J. G. Davis, IE N. C. Moseley, IE:II W. R. Butler, RL J. G. Keppler IE:III P. L. Richm, RL E. M. Howard, IE:IV J. M. Cutchin, RL R. H. Engelken. IE:V K. V. Seyfrit, IE T. Abell, MPIC G. W. Reinmuth, IE .

J. H. Sniczek, IE t