ML20057G224

Informs That NRC Reviewed Comparison Between Criteria in App F of USAR & Alternate Seismic Criteria & Methodology & Concurs W/Util Conclusion

ML20057G224
Person / Time
Site:	Fort Calhoun
Issue date:	10/18/1993
From:	Steven Bloom Office of Nuclear Reactor Regulation
To:	Tira Patterson OMAHA PUBLIC POWER DISTRICT
References
GL-87-02, GL-87-2, TAC-M69447, NUDOCS 9310210055
Download: ML20057G224 (4)

Text

-

October 18, 1993 Docket No. 50-285 Mr. Terry L. Patterson Division Manager - Nuclear Operation Omaha Public Power District 444 South 16th Street Mall Mail Stop 8E/EP 4 Omaha, Nebraska 68102-2247

SUBJECT:

EVALUATION OF CLARIFICATION OF 120-DAY RESPONSE TO SUPPLEMENT NO. 1 TO GENERIC LETTER 87-02 FOR FORT CALHOUN STATION (TAC NO. M69447)

By letter dated August 10, 1993, the NRC requested that the Omaha Public Power District (0 PPD) provide a comparison between the criteria in Appendix F of the Updated Safety Analysis Report (USAR) and the Alternate Seismic Criteria and Methodology (ASCM) so that the NRC can assess whether the in-structure response spectra generated on the basis of ASCM is " median centered." By letter dated September 24, 1993, you provided the comparison and concluded, on the basis of the NRC's review and approval of your July 31, 1992 letter, " Soil Variation Analyses and Generation of In-structure Response Spectra" as contained in NRC letter dated April 15, 1993, that the in-structure response spectra generated through ASCM should be more appropriately considered as i

" conservative design" rather than " median centered."

In view of this, OPPD stated that it intends to use ASCM spectra for all areas in the plant as

" conservative design" in-structure response spectra for resolving Unresolved l

Safety Issue A-46.

The NRC has reviewed the comparison and concurs with l

OPPD's conclusion. However, in using ASCM, OPPD is required to comply with the limitations imposed by the NRC as conditions of approval of the use of ASCM as indicated in our letter dated April 15, 1993.

Sincerely, ORIGINAL SIGNED BY:

Steven D. Bloom, Project Manager Project Directorate IV-1 l

Division of Reactor Projects - lil/IV/V Office of Nuclear Reactor Regulation cc: See next page DISTRIBUTION:

1 Docket File NRC & Local PDRs PD4-1 Reading S. Bloom E. Adensam W. Beckner P. Noonan ACRS(10) (P-315)

OGC(15818)

A. B. Beach, RIV J. Roe C. P. Tan 0FC LA:PD4-1 PM:PD4-1 D:PD4-1, a NAME PNoonanIM.SBlkpk WBeckner INff/93 10 / $/93 DATE D,/ J/93 J

COPY YESfb0 YESh10 YES(h i

NBC RLE CMTB NY 0FFICIAL RECORD COPY ument Name:

FC69447.ltr

/

9310210055 931018 hI J

rDR ADOCK 05000285 P

PDR

October 18, 1993 Docket No. 50-285 Mr. Terry L. Patterson Division Manager - Nuclear Operation Omaha Public Power District 444 South 16th Street Hall Mail Stop 8E/EP 4 Omaha, Nebraska 68102-2247

SUBJECT:

EVALUATION OF CLARIFICATION OF 120-DAY RESPONSE 10 SUPPLEMENT NO. 1 TO GENERIC LETTER 87-02 FOR FORT CALHOUN STATION (TAC NO. M69447)

By letter dated August 10, 1993, the NRC requested that the Omaha Public Power District (OPPD) provide a comparison between the criteria in Appendix F of the Updated Safety Analysis Report (USAR) and the Alternate Seismic Criteria and Methodology (ASCM) so that the NRC can assess whether the in-structure response spectra generated on the basis of ASCM is " median centered." By letter dated September 24, 1993, you provided the comparison and concluded, on the basis of the NRC's review and approval of your July 31, 1992 letter, " Soil Variation Analyses and Generation of In-structure Response Spectra" as contained in NRC letter dated April 15, 1993, that the in-structure response spectra generated through ASCM should be more appropriately considered as

" conservative design" rather than " median centered."

In view of this, OPPD stated that it intends to use ASCM spectra for all areas in the plant as

" conservative design" in-structure response spectra for resolving Unresolved Safety Issue A-46.

The NRC has reviewed the comparison and concurs with OPPD's conclusion. However, in using ASCM, OPPD is required to comply with the limitations imposed by the NRC as conditions of approval of the use of ASCM as indicated in our letter dated April 15, 1993.

Sincerely, ORIGINAL SIGNED BY:

Steven D. Bloom, Project Manager Project Directorate IV-1 Division of Reactor Projects - III/IV/V Office of Nuclear Reactor Regulation cc:

See next page DISTRIBUTION:

Docket File NRC & Local PDRs PD4-1 Reading S. Bloom E. Adensam W. Beckner P. Noonan ACRS(10) (P-315)

OGC(15B18)

A. B. Beach, RIV J. Roe C. P. Tan 0FC LA:PD4-1 PM:PD4-1 D:PD4-Ig n, PNoonarr@k SBlkpk NAME WBeckner DATE h / $293 ifhif/93 N/ M/93 YES1$b) kESh0 YES(fi)

COPY v

0FFICIAL RECORD COPY Document Name:

FC69447.ltr n

t

,pn arc o

/t UNITED STATES o

[,'gg f j t

Of NUCLEAR REGULATORY COMMISSION-gg

'j WASHINGTON D C. 20556-0001 s~;

"**+*

October 18, 1993 Docket No. 50-285 l

Mr. Terry L. Patterson Division Manager - Nuclear Operation Omaha Public Power District 444 South 16th Street Mall l

Mail Stop 8E/EP 4 Omaha, Nebraska 68102-2247

SUBJECT:

EVALUATION OF CLARIFICATION OF 120-DAY RESPONSE TO SUPPLEMENT NO. 1 TO GENERIC LETTER 87-02 FOR FORT CALHOUN STATION (TAC N0. M69447)

By letter dated August 10, 1993, the NRC requested that the Omaha Public Power District (OPPD) provide a comparison between the criteria in Appendix F of the Updated Safety Analysis Report (USAR) and the Alternate Seismic Criteria and Methodology (ASCM) so that the NRC can assess whether the in-structure response spectra generated on the basis of ASCM is " median centered." By letter dated September 24, 1993, you provided the comparison and concluded, on i

the basis of the NRC's review and approval of your July 31, 1992 letter, " Soil Variation Analyses and Generation of In-structure Response Spectra" as contained in NRr, letter dated April 15, 1993, that the in-structure respunse spectra generated through ASCM should be more appropriately considered as

" conservative design" rather than " median centered."

In view of this, OPPD stated that it intends to use ASCM spectra for all areas in the plant as

" conservative design" in-structure response spectra for resolving Unresolved Safety Issue A-46.

The NRC has reviewed the comparison and concurs with OPPD's conclusion.

However, in using ASCM, OPPD is required to comply with the limitations imposed by the NRC as conditions of approval of the use of ASCM as indicated in our letter dated April 15, 1993.

Sincerely, l

m l

a Steven D. Bloom, Project Manager l

Project Directorate IV-1 Division of Reactor Projects - III/IV/V Office of Nuclear Reactor Regulation l

cc: See next page t

b Mr. Terry L. Patterson Omaha Public Power District Fort Calhoun Station, Unit I i

cc:

Mr. Michael F. McBride, Esq.

LeBoeuf, Lamb, Leiby & MacRae 1875 Connecticut Avenue, NW Washington, D.C.

20009-5728 Mr. Jack Jensen, Chairman Washington County Board of Supervisors Blair, Nebraska 68008 Mr. Raymond P. Mullikin, Resident Inspector U.S. Nuclear Regulatory Commission Post Office Box 309 Fort Calhoun, Nebraska 68023 Mr. Charles B. Brinkman, Manager Washington Nuclear Operations Combustion Engineering, Inc.

12300 Twinbrook Parkway, Suite 330 Rockville, MD 20852 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 i

Arlington, Texas 76011 Harold Borchert, Director Division of Radiological Health Nebraska Department of Health 301 Centennial Mall, South Post Office Box 95007 l

Lincoln, Nebraska 68509 i

Mr. James W. Chase, Manager Fort Calhoun Station Post Office Box 399 Fort Calhoun, Nebraska 68023 i

l 1

1