ML20125C801

Forwards SE Accepting Util 920729 Revised Feedwater Nozzle Crack Growth Analysis for Plant,Per Generic Ltr 81-11

ML20125C801
Person / Time
Site:	Fermi
Issue date:	12/08/1992
From:	Colburn T Office of Nuclear Reactor Regulation
To:	Orser W DETROIT EDISON CO.
Shared Package
ML20125C803	List: ML20125C801 ML20125C804
References
GL-81-11, TAC-M84140, NUDOCS 9212140082
Download: ML20125C801 (4)

Text

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1. g UNITED STATES C [" > # g NUCLEAR PEGULATORY COMMISSION g, , t W ASHING TON, D. C. 20555

%.....'/ December 8, 1992 Docket No. 50-341 Mr. William S. Orser Senior Vice President - Nuclear Operations Detroit Edison Company 6400 North Dixie Highway Newport, Michigan 48166

SUBJECT:

FERMI-2 REVISED FEEDWATER N0ZZLE CRACK GROWTH ANALYSi$ PER GENERIC LETTER 81-11 (TAC N0. M84140)

By Vs Generic Ltr|letter dated July 29, 1992]], you provided for NRC review a revised feedwater nozzle crack growth analysis fcr Fermi-2. The revised analysis was a response to the NRC request that required Detroit Edison Company (Deco) to re-evaluate your original feedwater nozzle analysis. Your original growth analysis did not meet Generic Letter 81-11 criterion of limiting growth of a postulated 0.25 inch deep crack to a depth no greater than 1.0 inch in 40 years. Dur original analysis demonstrated that the postulated crack would grow to 1.0 inch in 8.9 operating years.

Your revised analysis demonstrates that the postulated crack would grow to a 1.0 inch depth in 38.3 years. This does not satisfy the crack growth criterion in Generic Letter 81-11. Nevertheless, we have determined that the methodology in the-analysis is acceptable because it is consistent with feedwater nozzle analyses that we have approved previously.

You stated that the thermal cycle projections used in the revised analysis are still conservative. Further, you believe that the actual number of thermal cycles will be less than projected and that this will result in a calculated crack growth to no greater than one inch in 40 years. However, the staff requires confirmation of this growth analysis when more operating data on thermal cycles are available and -submit the analysis for NRC review six months prior to the end of 12 operating years.

The details of our review are contained in the enclosed Safety Evaluation.

ID 100018 pt 1

Q 9212140082 921208 DR ADOCK 0500 g1

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2 The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents, therefore, OMB clearance is not required under P.L.96-511. If you have any questions, please call me at (301) 504-1341.

Sincerely, Original signed by:

Timothy G. Colburn, Sr. Project Manager Project Directorate 111-1 Division of Reactor Projects - lil/lV/V Office of Nuclear Reactor Regulation -

Enclosure:

Safety Evaluation cc w/ enclosure:

See next page DISTRIBUTION:

Docket File-PDR Reading File JRoe JZwolinski LMarsh MShuttleworth TColburn OGC JTsao 7D4 _

ACRS (10)

Plant File WShafer Rlli cc: Plant Service List 0FFICE LA:PDIll-1 PM:PDill-1 PD:PDlII-l NAME MShuttle M k TColburn:)my LMarsh liEc-g& ~

l DATE /c/:U92 'O /'/92 /2 / &~/92 FILENAME:G:\WPDOCS\ FERMI \fE84140.LTR q i

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,.o J ,' 2 The reporting and/or recordkeeping requirements contained in this letter affect fewer than ten respondents, therefore, OMB clearance is not required under P.L.96-511. If you have any questions, please call me at (301) 504-1341.

Sincerely, bW Timothy G. Colburn, Sr. Project Manager Project Directorate 111-1 Division of Reactor Projects - III/IV/V Office of Nuclear Reactor Regulation

Enclosure:

Safety Evaluation cc w/ enclosure:

See next page

f-

-1 Mr. William Orser Fermi-2 I Detroit Edison Company <

l cC; John Flynn, Esquire Senior Attorney Detroit Edison Company 2000 Second Avenue Detroit, Michigan 48226 Nuclear Facilities and Environmental Monitoring Section Office Division of Radiological Health -

Department of Public Health 3423 N. Logan Street P. 0. Box 30195 Lansing, Michigan 48909 Mr. Stan Stasek U.S. Nuclear Regulatory Commission ,

Resident inspector Office 6450 W. Dixie Highway Newport, Michigan 48166 Monroe County Office of Civil Preparedness 963 South Raisinvile Monroe, Michigan 48161 Regional Administrator, Region til U.S. Nuclear Regulatory Commission 799 Roosevelt Road ~

Glen Ellyn, Illinois 60137 Mr. A. Cacil Settles Director - Nuclear Licensing Detroit Edison Company Fermi 2 6400 North Dixie Highway Newport, Michigan 48166