ML20045A869

Discusses Util 870219 Commitments to Address & Close Out Staff Concerns Re Hydrogen Rule (10CFR50.44) Raised During Discussions Prior to Restart from Plant Shutdown in 1985

ML20045A869
Person / Time
Site:	Sequoyah
Issue date:	06/09/1993
From:	Labarge D Office of Nuclear Reactor Regulation
To:	Medford M Tennessee Valley Authority
References
TAC-R00356, TAC-R00357 NUDOCS 9306150146
Download: ML20045A869 (5)

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/ "i UNITED STATES f

.E NUCLEAR REGULATORY COMMISSION k

WASHINGTON, D.C. 20655 s..w...]

June 9, 1993 Docket Nos. 50-327 and 50-328 l

1 Dr. Mark 0. Medford, Vice President l

Technical Support Tennessee Valley Authority 3B Lookout Place 1101 Market Street Chattanooga, Tennessee 37402-2801 i

SUBJECT:

CLOSE0VT OF HYDROGEN CONTROL RULE (10 CFR 50.44) IMPLEMENTATION AT THE SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 (TAC N05. R00356 AND l

R00357)

By letter dated February 19, 1987, the Tennessee Valley Authority (TVA) 3 submitted a plan of action and comitments to address and close out staff concerns related to the hydrogen rule (10 CFR 50.44) that had been raised 5

during discussions prior to restart from the plant shutdown in 1985. These comitments are listed in the enclosure to this letter. The implementation dates given for these comitments were contingent upon the availability of i

reports and submittals related to the subject that were to be made available to TVA by the Duke Power Comoany.

l By letter dated March 31, 1987, the NRC staff indicated that these commitments i

were acceptable and that the p"oposed schedule for implementation was adequate to support restart of Setuoyah P.'ite 1 and 2.

l By letter dated January 29, 1988, TVA re-confirmed the comitments and informed the staff that the schedule could not be met because the information from the Duke _ Power Company was iot available.

By letter dated November 21, '.989, TVA responded to Generic Letter 89-21,

" Request for Information Concerning Status of Implementation of Unresolved Safety Issue (USI)_Requirem(nts" for the Sequoyah Nuclear Plant.

For USI A-48, " Hydrogen Control Mea;ures and Effects of Hydrogen Burns on Safety I

Equipment," TVA indicated. hat future analytical work was planned. _ -The i

schedule for this work effort and the comitments mentioned ~above were tied to t

the completion of analytical work being ' performed by the Duke Power Company.

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Resolution of USI A-48 is described in, and is the subject of, NUREG-1370. An acceptable means'of imp 1 ementing A-48 consistent with 10 CFR 50.44 for ice 1

condenser facilities, ccasists of installation of a hydrogen igniter system i

and the performtace c; additional confirmatory research relating to equipment survivability. Ti.e Sequoyah Nuclear Plant currently has an operable hydrogen igniter _ system, as approved by the staff in a safety evaluation dated D(-

February 22, 1988.

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2' PDR ADDCK 05000327 b^#" *"'" #

P PDR l

Dr. Mark O. Medford !

i By letter dated September 28, 1992, TVA submitted an additional hydrogen rule l

analysis, which evaluated the reanalysis performed by the Duke Power Company for the Catawba Nuclear Plant that was supplied to TVA on March 10, 1992.

The Duke Power analysis concluded that the reanalysis performed using a different computer code continued to demonstrate the survival of equipment in the i

containment when subjected to the environment resulting from hydrogen buros.

The TVA analysis determined that the containment and equipment responses associated with the Catawba Station describcd in the Duke report were applicable to Sequoyah. Also, since the original analyses performed by both TVA and the Duke Power Company were comparable, it is expected that if a i

Sequoyah-specific analysis was performed, similar results would be obtained.

In addition, the four degraded core sequences selected by Duke for the Catawba analysis that were determined to be the dominant sequences for hydrogen generation, are the same sequences identified in the Individual Plant Evaluation (IPE) performed in accordance with Generic Letter 88-20 and submitted by TVA's letter of September 1,1992.

j The staff has reviewed the " Technical Report on Hydrogen Control Measures and Effects of Hydrogen Burns on Safety Equipment" report forwarded by your September 28, 1992 letter.

Based on this report, the February 19, 1987 restart commitments are considered to be fulfilled. Also, the requirements of NUREG-1370 are considered to be fulfilled and the previous conclusions of SSER-6 reconfirmed.

Based on this information and other relevant information, the staff has

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determined that TVA has adequately addressed the hydrogen generation and control concerns for the Sequoyah Nuclear Plant containment and considers the Hydrogen Rule (10 CFR 50.44) and USI A-48 to be closed for the Sequoyah i

Nuclear Plant, Units 1 and 2.

Sincerely, Original signedby i

David E. LaBarge, Senior Project Manager Project Directorate 11-4 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Enclosure-Hydrogen Rule Commitments cc w/ enclosure:

See next page OFC PDII-4/LA PDII-4/PMdr, SCSB PDI H /D NAME MSanders:a}

DLaBarge RLobel FH5No'n F

i DATE

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-Tennessee Valley Authority-Sequoyah Nuclear Plant ATTN:

Dr. Mark 0.-Medford CC:

Mr. W. H. Kennoy, Director' County' Judge Tennessee Valley Authority Hamilton County Courthouse ET 12A Chattanooga, Tennessee-37402 400 West Summit Hill Drive Knoxville, Tennessee 37902 Regional Administrator _.

i U.S.N.R.C, Region 11 Mr. R. M. Eytchison,.Vice President 101 Marietta Street, N.W.-

i Nuclear Operations Suite 2900 j

Tennessee Valley Authority Atlanta, Georgia 30323 3B Lookout Place 1101 Market Street 1

Chattanooga, Tennessee 37402-2801 1

Mr. William E. Holland Senior Resident. Inspector-Sequoyah Nuclear Plant Mr. M. J. Burzynski, Manager U.S.N.R.C.

Nuclear Licensing and Regulatory Affairs-2600 Igou Ferry Road Tennessee Valley Authority Soddy Daisy, Tennessee 37379 SB Lookout Place

'i 1101 Market Street i

Chattanooga, Tennessee 37402-2801 l

Mr. Jack Wilson, Vice President Sequoyah Nuclear Plant Tennessee Valley Authority P.O. Box 2000 Soddy Daisy, Tennessee 37379 TVA Representative Tennessee Valley Authority 11921 Rockville Pike i

Suite 402 i

Rockville, Maryland 20852 l

Ms Marci Cooper, Site Licensing Manager Sequpyah Nuclear Plant Tennessee Valley Authority

-l P.O. Box 2000 j'

Soddy Daisy, Tennessee 37379 i

Mr. Michael H. Mobley, Director l

Division of Radiological Health 3rd Floor,'t and C Annex i

401 Church Street Nashville, Tennessee 37243-1532 General Counsel Tennessee Valley Authority ET'llH-400 West-Summit Hill Drive Knoxville, Tennessee 37902 j

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t ENCLOSURE SE0VOYAH NVCLEAR PLANT UNITS 1 AND 2 i

ADDITIONAL HYDROGEN RULE ANALYS11

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COMMITHENTS AS STATED IN TVA LETTER DATED FEBRUARY 19. 1987 TASK Contract with Duke Power to obtain all work submitted by Duke to NRC on April 25, 1986.

Obtain all applicable reports and complete review for applicability to Sequoyah.

Transmit report to NRC on applicability of Duke Power work on hydrogen rule to Sequoyah.

Transmit report to NRC that addresses and analyzes issues not addressed by.

Duke Power work so as to close all open issues.

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.- Distribution Docketdil;@

NRC & Local PDRs SQN Reading S. Varga G. Lainas F. Hebdon M. Sanders D. LaBarge R. Lobel 0GC ACRS (10)

E. Merschoff, RII P. Fredrickson, RII P. Kellogg, RII