ML20203E135

Forwards Safety Evaluation Accepting Re Approval of Realistic,Median Centered Spectra Generated for Resolution of USI A-46

ML20203E135
Person / Time
Site:	Millstone
Issue date:	02/09/1998
From:	Stephen Dembek NRC (Affiliation Not Assigned)
To:	Bowling M NORTHEAST NUCLEAR ENERGY CO.
Shared Package
ML20203E140	List: ML20203E135 ML20203E244
References
REF-GTECI-A-46, REF-GTECI-SC, TASK-A-46, TASK-OR TAC-M69458, NUDOCS 9802260269
Download: ML20203E135 (6)

Text

_ _ _ _ _ _ - _ _ -

Mr. Martin L. Bowling February 9, 1998

?

Recov:ry Of,.cer- Millston]

Unit Ni 2

, Northeast Nuclear Energy Company c/o Ms. Patricia A. Loftus Director- Regulatory Affairs P. O. Box 128 Waterford, CT 06385

SUBJECT:

MILLSTONE NUCLEAR POWER STATION, UNIT 1 APPROVAL OF THE REALISTIC, MEDIAN CENTERED SPECTRA GENERATED FOR THE RESOLUTION OF UNRESOLVED SAFETY ISSUE (USI) A-46 ISSUES (TAC NO. M69458)

Dear Mr. Bowling:

In a September 26,1995, letter, the Northeast Nuclear Energy Company (NNECO) requested NRC staff review and approval of NNECO's approach for developing realistic, median centered in-structure response spectra for the Millstone Ur.it No.1 reactor, auxiliary radwaste/ control and turbine buildings, in a June 4,1996, letter, the NRC staff requested additional information (RAI) to complets the staff's review. NNECO responded to the staff's RAI in an October 17,1996, letter.

The NRC staff has completed its review of the material submitted by NNECO. The NRC staff concluded that NNECO's seismic analysis approach and the assumptions used in the analytis

! are consistent with Standard Review Plan Section 3.7.1 guide'ines for multiple time history

{ analysis. They are also judged as consistent with the applicable Millstone 1 licensing basis and the Generic Implementation Procedure, Revision 2 guidelines provided for the generation of realistic, median centered in-structure response spectra for resc:ution of UCI A-46 issues.

Therefore, NNECO's approach is acceptable.

Sincerely, Original signed by:

Stephen Dembek, Project Manager Special Projects Office - Licensing Office of Nuclear Reactor Regulation Docket No. 50-245

Enclosure:

Safety Evaluation  !/

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...../ February 9, 1998 Mr. Martin L Bowling Recovery Officer- Millstona Unit No. 2 Northeast Nuclear Energy Company .

clo Ms. Patricia A. Loftus Director- Regulatory Affairs P. O. Box 128 Waterford, CT 06385

SUBJECT:

MILLSTONE NUOLEAR POWER STATION, UNIT 1 - APPROVAL OF THE REALISTIC, MEDIAN CENTERED SPECTRA GENERATED FOR THE RESOLUTION OF UNRESOLVED SAFETY ISSUE (USI) A-46 ISSUES (TAC NO M69458)

Dear Mr. Bowling:

in a September 26,1995, letter, the Northeast Nuclear Energy Company (NNECO) requested NRC staff review and approval of NNECO's approach for developing realistic, median centered in-structure response spectra for the Millstone Unit No.1 reactor, auxiliary radwaste/ control and turbine buildings. In a June 4,1996, letter, the NRC staff requested additionalinformation (RAI) to complete the staffs review. NNECO responded to the staffs RAIla an October 17,1996, letter.

The NRC staff has completed its review of the me.terial submitted by NNECO. The NRC staff concluded that NNECO's seismic analysis approach and the assumptions used in the analysis are consistent with Standard Review Plan Section 3.7.1 guidelines for multiple time history analysis. They are also judged as consistent with the applicable Millstore i liceraing basis and the Generic implementation Procedure, Revision 2 guidelines provided for tha generation of realistic, median centered in structure responae spectra for resolution of U' . s-46 issues.

Therefore, NNECO's approach is acceptable.

Sincerely, j <- J Stephen Dembek, Project Manager Special Projects Office - Licensing Office of Nuclear Reactor Regulation Docket No. 50 245

Enclosure:

Safety Evaluation -

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