ML20212M560

Advises That 840914,850102 & 1108 Supplemental Cycle 6 Analyses Sufficient for Satisfying NRC Request for Confirmatory Calculations.Acceptance of Retran Model Should Not Be Construed as Acceptance for Future Licensing

ML20212M560
Person / Time
Site:	Millstone
Issue date:	01/21/1987
From:	Jaffe D Office of Nuclear Reactor Regulation
To:	Mroczka E NORTHEAST NUCLEAR ENERGY CO.
References
TAC-54199, NUDOCS 8701300161
Download: ML20212M560 (2)

Text

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January 21, 1987 Distribution Docket No. 50-336

' Docket File ACRS (10)

NRC/ Local POR PKreutzer PBD-8 Reading DJaffe FMiraglia OGC-Beth Mr. Edward J. Mroczka, Senior Vice President EJordan NThompson Nuclear Engineering and Operations BGrimes JPartlow Northeast Nuclear Energy Company Gray File 3.5a P. O. Box 270 Hartford, Connecticut 06141-0270

Dear Mr. Mroczka:

By [[letter::B10987, Forwards ASME Section Iii,Class 2 & 3 & ANSI B31.1.0 Piping Analysis, Ultrasonic Indications in Steam Generator Top Head Dome Weld. Evaluation Verified Structural Integrity of Plant Steam Generators,Per NRC|letter dated December 30, 1983]], the NRC staff forwarded Amendment No. 90 to Facility Operating License No. DPR-65.

The amendment authorized Cycle 6 operation for Millstone Unit No. 2.

The NRC Safety Evaluation accompanying the amendment addressed various aspects of the evaluations submitted to support Cycle 6 operation.

The staff documented several concerns relating to the analysis of steam line breaks and steam generator tube ruptures and requested that these concerns be addressed by confirmatory calculations.

The staff's concerns included the possible effect of a loss of of fsite power coincident with these analyzed events and the mixing factors considered in the steam line break analysis.

The staff has reviewed the supplemental Cycle 6 analyses provided in letters dated September 14, 1984, January 2, and November 8, 1985, and has concluded that these analyses are sufficient for satisfying our request for confirmatory calculations. We note, however, that the steam generator tube rupture was performed using a RETRAN model for Millstone Unit No. 2.

While we find that this model was adequate for responding to our request, our acceptance of this calculation should not be construed as an acceptance of the Millstone Unit No. 2 RETRAN model for future licensing analyses.

Should NNECo decide to utilize the RETRAN code for future licensing analyses, you should submit the Millstone Unit No. 2 RETRAN model for staff review and approval at that time.

Based upon the above, we consider the issue of supplemental Cycle 6 analyses to be closed.

I l

Sincerely,

/s/

D. H. Jaffe, Project Manager PWR Project Directorate #8 Division of PWR Licensing-B cc:

See next page 0701300161 070121 PDH ADOCK 05000336

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Mr. Edward J. Mroczka Millstone Nuclear Power Station Northeast Nuclear Energy Company Unit No. 2 cc:

Gerald Garfield, Esq.

Mr. Stephen E. Scace Day, Berry & Howard Superintendent Counselors at Law Millstone Nuclear Power Station City Place P. O. Box 128 Hartford, Connecticut 06103-3499 Waterford, Connecticut 06385 Regional Administrator, Region I Mr. Wayne D. Romberg U.S. Nuclear Regulatory Commission Vice President, Nuclear Operations Office of Executive Director for Northeast Nuclear Energy Company Operations P. O. Box 270 631 Park Avenue Hartford, Connecticut 06141-0270 King of Prussia, Pennsylvania 19406 Mr. Charles Brinkman, Manager Washington Nuclear Operations C-E Power Systems Combustion Ergineering, Inc.

7910 Woodmont Avenue Bethesda, Maryland 20814 Mr. Lawrence Bettencourt, First Selectman Town of Waterford Hall of Records - 200 Boston Post Road Waterford, Connecticut 06385 Northeast Utilities Service Company ATTN:

Mr. Richard M. Kacich, Manager Generation Facilities Licensing Post Office Box 270 Hartford, Connecticut 06141-0270 Kevin McCarthy, Director Radiation Control Unit Department of Environmental Protection State Office Building Hartford, Connecticut 06106 Mr. Theodore Rebelowski U.S. NRC P. O. Box 615 Waterford, Connecticut 06385-0615 Office of Policy & Management ATTN:

Under Secretary Energy Division 80 Washington Street Hartford, Connecticut 06106

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