ML20245E688

Forwards Safety Evaluation Re microbiologically-induced Corrosion Program.Inclusion of Structural Sleeve Weld Repair Method in Util Original Request for Relief & Corrosion Program Acceptable

ML20245E688
Person / Time
Site:	Sequoyah
Issue date:	08/03/1989
From:	Black S Office of Nuclear Reactor Regulation
To:	Kingsley O TENNESSEE VALLEY AUTHORITY
Shared Package
ML20245E692	List: ML20245E688 ML20245E695
References
TAC-R00494, TAC-R00495, TAC-R494, TAC-R495, NUDOCS 8908110328
Download: ML20245E688 (3)

Text

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9NITED STATES

,[ ' .-. j NUCLEAR REGULATORY COMMISSION

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.  ; . WASmGTON, D. C. 205$5

% . i h . .', '. . # August 3, 1989 '

p Docket hos. 50-327 and 50-328 i

L  !

Mr. Oliver D. Kingsley, Jr.

Senior Vice Presioent, Nuclear Power Tennessee Valley Authority L

6N 38A Lookout Place 1101 Market Street Chattanooga, Tennessee 37402-2801

SUBJECT:

MICROBIOL0GICALLY INDUCED CORROSION PROGRAM (TAC NOS. R00494/R00495) -

SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 i-

.Ey letter datec January 20, 1988, the Tennessee Valley Authority (TVA) sub-mitted a microbiologically induced corrosion (MIC) program for Sequoyah. The .

MIC damage was in the essential raw cooling water system. The staff accepted the program in its letter dated March 31, 1988, noting that not repairing or replacing MIC damaged welds when found would require the granting of relief from certain American Society for Mechanical Engineers Boiler and Pressure Vessel Code,Section XI (Code) inservice inspection requirements, i.e., repair of leaking welds to Code criteria. The original request for relief from thc Code,Section XI, IWA-5250(a)(2) for this subject was made in the TVA letter cated April 4,1988, with two clarification letters dated April 4, and May 4,  ;

1988. The request for relief was granted by NRC in its letter cated May 11, '

1988, on the condition that three additional requirements were incorporated in TVA's MIC program.

By letter dated October 28,1988, TVA (1) implicitly requested the inclusion of a contingent, temporary structural sleeve weld repair method for MIC damage under the eelief granted by our letter of May 11,1988,(2) acknowledged the three additional requirements in our May 11, 1988 letter and addressed how they were implemented, and (3) descrit,ed TVA's contingency plan for installing a ,

structural sleeve as a temporary repair. The sleeve weld repair is a temporary measure for the plant to complete its operating cycle and would be replaced by a Code approved permanent repair in the next refueling outage. In a telephone t% , conversation with NRC staff on June 12, 1989, TVA clarified technical aspects discussed in the letter. '

nn{z l gga. The staff has considered the inclusion of this structural sleeve weld repair oo method in TVA's original request for relief and finds it is acceptable. The

$$ staff also finds that TVA has acceptably implemented the additional require-eg ments in our May 11, 1988 letter and the MIC program is acceptable. The bases gg for our conclusions are provided in the enclosed Safety Evaluation (SE). The oc stuff concludes that the Code repair requirements of MIC damage (leaks and 5

m structural integrity loss) within stated limits of ERCW piping welds while the plant is in its operating cycle are impractical and that, pursuant to 10 CFR m$a.a.

50.55a(a)(3)(1), the MIC program including the temporary weld repair method MI proposed by TVA will provide an acceptable level of quality and safety. ,

I Mr. Oliver D. Kingsley,.Jr. * '

I The staff also concludes that the repair method will not endanger life or property, or the common defense and security and is othcrwise in the public interest considering the burden that coald result upon TVA if the Code require-h T.erefore, ments were imposed upon the Sequoyah Nuclear Plant, Units 1 and 2.

the staff concludes that (1) the basis for granting the relief in the staff's letter dated May 11, 1988 has not changed and (2) the TVA proposed sleeve repair is within the previous relief from the Code,Section XI. IWA-5250(a)(2) which was granted to TVA for Sequoyah in the staff's letter dated May 11, 1988 and that no new relief from the Code need be granted.

Siacerely, l Original Signed by i Gerald E. Gears for Suzanne Black, Assistant Director for Projects TVA Projects Division Office of Nuclear Reactor Regulation

Enclosure:

l Safety Evaluation cc w/ enclosure:

See next page Distribution Docket File NRC PDR Local PDR Projects Reading ADSP Reading D. Crutchfield B. D. Liaw S. Black R. Pierson B. Wilson L. Watson J. Brady W. S. Little M. Simms J. Donohew OGC S, Zwolinski E. Jordan D. Smith D. Terao ACRS (10)

GPA/CA SQN Rdg. File OFC :NRR:TVA/LA :N :I M' :T VAM: AD/TP, TVA:AD/P  :  :  : :

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NAME :MSimms J w:at, :RPierson SB .

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DATE :7Af)/89 :7/li/89 :7/H/89 :S .

0FFICIAL RECORD COPY

4 Mr..0 liver D. Kingsley, Jr.

. CC:

General Counsel- Mr. Kenneth M. Jenison Tennessee Valley Authority Senior Resident Inspector 400 West Summit Hill Drive Sequoyah Nuclear Plant ET 118 33H U.S. Nuclear Regulatory Commission Knoxville. Tennessee 37902 2600 Igou Ferry Road Soddy Daisy, Tennessee 37379 Mr. F. L. Moreadith Vice President, Nuclear Engineering Mr. Michael H. Mobley, Director Tennessee Valley Authority Division of Radiological Health 400 West Summit Hill Drive T.E.R.R.A. Building, 6th Floor WT 12A 12A 150 Oth Avenue North Knoxville, Tennessee 37902 Nashville, Tennessee 37219-5404 Dr. Mark 0. Medford Dr. Henry Myers, Science Advisor Vice President and Nuclear Committee on Interior Technical Director and Insular Affairs Tennessee Valley Authority U.S. House of Representatives 6N 38A Lookout Place Washington, D.C. 20515 Chattanooga, Tennessee 37402-2801 Tennessee Valley Authority .

Manager, Nuclear Licensing Rockville Office and Regulatory Affairs 11921 Rockville Pike Tennessee Valley Authority Suite 402 SN 157B Lookout Place Rockville, Maryland 20852 Chattanooga, Tennessee 37402-2801 Mr. John L. LaPoint Site Dir.ector Sequoyah Nuclear Plant '

Tennessee Valley Authority P. O. Box 2000 Soddy Daisy. Tennessee '37379 Mr. M. Burzynski Acting Site Licensing Manager Sequoyah Nuclear Plant P. D. Box 2000 Soddy Daisy, Tennessee 37379 County Judge Hamilton County Courthouse Chattanooga, Tennessee 37402 Regional Administrator, Region II U.S. Nuclear Regulatory Commission 101 Marietta Street, N.W.

Atlanta, Georgia 30323

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