JPN-93-084, Responds to Potential Concern Identified by NRC W/Depth of Concrete Between Bottom of Drywell Sump & Containment Liner Beneath,In Connection W/Nrc Review of Util 920901 Response to NRC RAI on Individual Plant Exam Provided Via

Responds to Potential Concern Identified by NRC W/Depth of Concrete Between Bottom of Drywell Sump & Containment Liner Beneath,In Connection W/Nrc Review of Util 920901 Response to NRC RAI on Individual Plant Exam Provided Via

ML20062M198
Person / Time
Site:	FitzPatrick
Issue date:	12/28/1993
From:	Ralph Beedle POWER AUTHORITY OF THE STATE OF NEW YORK (NEW YORK
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
JPN-93-084, JPN-93-84, NUDOCS 9401060257
Download: ML20062M198 (2)

Text

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December 28,1993 JPN-93-084 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Station P1-137 Washington, DC 20555

SUBJECT:

James A. FitzPatrick Nuclear Power Plant Docket No. 50-333 Individual Plant Examination

References:

1. NYPA letter, R. E. Beedle to the NRC dated September 1,1992 (JPN-92-046), providing NYPA's response to an NRC Request for Additional Information on the Individual Plant examination for the FitzPatrick Nuclear Power Plant.

2. NYPA letter, R. E. Beedle to the NRC dated September 13,1991 (JPN-91-048), providing the Individual Plant Examination for the FitzPatrick Nuclear Power Plant.

Dear Sir-During the NRC's review of the Authority's response to a Request for Additional information on the FitzPatrick Individual Plant Examination (IPE) (References 1 ano 2), .

the NRC identified a potential concem with the depth of concrete between the bottom of the drywell sump and the containment liner beneath. In the highly unlikely event of a core-melt accident which propagates through the bottom of the reactor vessel, the molten core debris would collect in the drywell sumps located beneath the reactor.

Localized molten core-concrete interactions (MCCl) may thus ablate the floor and possibly fail the containment liner. The distance between the bottom of the sump and the containment liner beneath was stated erroneously in Reference 1, Response to item 25 as being "only a few inches."

A recent review of plant drawings has determined that the actual distance between the bottom of the drywell sump and the containment liner beneath is ,

4 ft.- 8 in. at the reactor center line, not "a few inches" as described in the IPE RAI .1 response quoted above. The clarification makes the containment failure scenario  !

described above even more unlikely. This containment failurs mode was not j considered generically by the NRC in NUREG/CR-5423, and the FitzPatrick IPE likewise did not consider this scenario in the quantification of the IPE results. Since this containment failure scenario was not quantified in the IPE, this new information has no effect on the numeric or qualitative results of the IPE. .- )

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I i . If you have any questions, please contact Mr. J. A. Gray, Jr.

{ Very truly yours,  :

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Ralph E. e j 1

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! cc: Regional Administrator '

j U.S. Nuclear Regulatory Commission i 475 Allendale Road i

! King of Prussia, PA 19406 l 1 i

) Office of the Resident inspector U.S. Nuclear Regulatory Commission P.O. Box 136 Lycoming, NY 13093 Mr. Brian C. McCabe Project Directorate 1-1 j Division of Reactor Projects - 1/11 U.S. Nuclear Regulatory Commission l Mail Stop 14 Washington, DC 20555 Mr. John O. Schiffgens Office of Nuclear Reactor Regulation i Risk Applications Branch i U.S. Nuclear Regulatory Commission Mail Stop 10-E4 Washington, DC 20555

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