ML20215D180

Summary of 870518-20 Meetings W/Util in Framingham,Ma Re Review of Design Code Changes & Load Combinations.Licensee Agreed to Provide Written Responses to Agenda Questions Documenting Discussions During Meeting.W/O Encl

ML20215D180
Person / Time
Site:	Yankee Rowe
Issue date:	06/04/1987
From:	Mckenna E Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 8706180425
Download: ML20215D180 (2)

Text

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a JUN 0 41987 1 I

Docket No.50-029 LICENSEE: Yankee Atomic Electric Company (YAEC) ,

FACILITY: Yankee Nuclear Power Station

SUBJECT:

Meetirg Summary - May 18 to 20, 1987 l On May 18 through 20, 1987, members of the NRC staff met with representatives of )

YAEC in Framingham, Massachusetts to discuss.the review of design code changes 1

!and load combinations. The list of attendees is provided in Enclosure 1. The list of topics for discussion was transmitted with the meeting notice; the meet- l

)

c ing agenda for response to the topics is in Enclosure 2.

)

As noted in the agenda, there are three major review areas: snow loads, code q changes affecting structural elements, and load combinations. The review meeting included both licensee presentation of analyses and audits of the calculations. I i

The staff evaluated the vapor container capital under the combined loading of a i loss-of-coolant accident (LOCA) and a seismic event (NRC loading). For the  !

shell cway from the penetrations, the columns, the horizontal beams and the t tie rods, the data provided in the seismic evaluation report of the VC (March l 1984) was sufficient to establish acceptability. Anchor bolts and the joints 1 between' column and shell needed further review as data was not available in d the rcport.

)

The licensee performed an evaluation which takes into account the fact that for a seismically induced LOCA, peak accident conditions (temperature / pressure) are tot reached simultaneously with the strong earthquake motion. This evalua-tion is based on the assumption that the earthquake loading will initiate the LOCA, Under the conditions of the earthquake and the temperature / pressure that would exist when the earthquake excitation stopped, the structural integrity is ,

maintained. The staff agreed that this seemed a reasonable approach, but spe- I cific details, such as the duration of the earthquake motion, needed to be worked out.

For those structural elements in existing structures that were checked to show that newer code requirements were satisfied, the licensee provided calculations for staff audit. A few items were identified (S4, SS and C5) for additional licensee action.

1 Snow loads on the fire water tank were also discussed. The licensee discussed their basis for the loading profile applied on the tank roof. Because of the geometry (slope, no parapets), the licensee concluded that the loading on the ).

edge would be less than the uniform 125 psf extreme snow load. The staff will evaluate the licensee's justification. y l

P h6 g5870604 i 05000029 I PDR l

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i In~ sumary, the licensee. agreed to provide written responses to the agenda

' questions that would document the discussions during the meeting.

/5 Eileen McKenna, Project Manager Project Directorate.I-3 Division of Reactor Projects I/II

Enclosures:

. As stated cc w/ enclosures:

see next page Distribution

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NRC PDR i L Local PDR PDI-3 r/f PDI-3 s/f  !

VNerses EMcKenna OGC-Bethesda EJordan JPartlow ACRS(10)

NRC Participants

'(cc: Licensee and Plant Service List) i Office:

Name:

P MQ EtcKenna

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Date: 06/3 /87 W/p/87