ML17297A393

Revised Final Deficiency Rept Re Unconservative Loads on Pipe Support Design Mods,Initially Reported on 801217. Drawings W/Load Discrepancies Being Evaluated on case-by-case Basis to Determine If Redesign Is Necessary

ML17297A393
Person / Time
Site:	Palo Verde
Issue date:	04/28/1981
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
10CFR-050.55E, 10CFR-50.55E, SQRD-50-328-81, NUDOCS 8105050559
Download: ML17297A393 (6)

Text

REOULAT( INFORMATION DISTRIBUTIONSTEM (RIBS)

ACCESSION NBR $ 8105050559 DOC ~ DATE.S 81/04/28 NOTARIZED! NO DOCKET FACIL~iSTN 50 528 Palo Verde, Nuclear, Station~

AUTH ~ NAME'- AUTHOR AFF ILIAT'ION Unit ii Arizona Publi 05000528 MILLSr L "s M s Tennessee Valley Authority RECIP ~ NAME< RECIPIENT AFFILIATION 0'RE ILLY g J's P ~ Region 2r Atlanta< Office of the Dir ector SUBJECT! Revised final deficiency r ept- r'e unconservative loads on pipe suppor t design modsiinitial ly r eported on 801217.

Drawings w/'load discrepancies are bing evaluated on case by ease( basis to determinel if r edesign is necessary+

DISTRIBUTION CODE( ~ B0 1 9S COP IES RECEI VED! L~TR <<<<" ENCL SIZE ~

Constr'uction Deficiency Report (10CFR50 ~ 55E) 'ITLE!

NOTES!Standardized Plant;1 cy.'C'r imes 05000528 REC IPIENT COPIES RECIPIENT COPIES ID CODE/NAME) LTTR ENCLl ID CODE/NAME L'TTR ENCL" ACTION:. A/D LICENSNG 04 1 LIC BR 03 BC 05 1 1 LIC BR N3 LA 1 KERRIGANr J ~ 07 1 1 ASLBP/JBHARD ISE'9 D/DIR HUM FAC15 06'NTERNAL:

1 1 1 1 EDO L STAFF 19 1 EQUIP QUAL BR11 1 1 HYD/GEO BR 22 1 1 1 1 IE'/EES 1 L'IC QUAL BR 12 1 1 MPA 20, 1 1 NRC PDR 02' OELD 21 1 1 REV 13 1 1 QA BR 14 1 1 EG FILE( 01 1 1 RUTHERFORDgH ~ IE( 1 EV 21 1 1 EXTERNAL's ACRS 16'8 16 16 LPDR 03 1 1 NSIC 1 1 K

TOTAL NUMBER OF COPIES REQUIREDB LTTR ENCL

E

~ ~ bl b

V b

7s TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II April 28, 1981 SQRD-50-328/81-08

~3' (

Mr. James O'Reilly, Director

'Office of Ins tion and Enforcement U.S. Nuclear atory Camission Region II Suite 100 101 Marietta Street Atlanta, Georgia 303

Dear Mr. O'Reilly:

SHQUOGQi KKKZAR PLANT UNIT 2 LCADS ON PIPE SUPPORP DESIGN MODIFICATICNS SQRD"50-328/81-08 - REVISED FINAL REPORT h The subject deficiency was initially reported to NRC-OIE Inspector R. W. Wright on December 17, 1980, in accordance with 10 CFR 50.55(e) as NCR SQN CEB 8039. This was follcxmd by our interim reports dated January 19 and March 2, 1981. A final report was submitted April 1, 1981.

Enclosed is our revised final report. We inadvertently deleted the last line of the corrective action fran our final report.

If you have any questions, please get in touch with D. L. L-anlmrt at PXS 857-2581.

Very truly yours, TIMGKSEE VALXZY AUTHOR'S L. M. Mills, Manager Nuclear Regulation and Safety Enclosure-cc: Nr. Victor Stelio, Director (Encloeore)

Office of Inspection and Enforcement g

U.S. Nuclear Regulatory Camission Washington, DC 20555 go/1 5

An Equal Opportunity Employer

P'I VV I T 4

I P C

L ai

~st ~ ~

1 0 EHCEtOSURE SHQUOYAH NUCLFAR PLANT UNIT 2 UNCONSERVATIVE LOADS ON PIPE SUPPORP DESIGN MODIFICATIONS SQRD-50-328/81-08 10 CFR 50.55(e)

REVISED FINAL REPORP Descri tion of Deficie Piping system analyses and support design for class 1, 2, and 3 systems inside containment were contracted out to EDS Nuclear, Incorporated. EDS tabulated design loads for the pipe supports on support drawings. EDS had design and revision responsibility for all piping reanalysis results which could have an impact on existing support designs. Load increases that resulted from piping reanalyses but did not require design modifications were not revised on the support drawings. Design control responsibility for all supgort drawings was subsequently turned over to TVA, and subsequent design modifications by TVA were based on the design loads tabulated on the drawings. .Therefore, scme design modifications by TVA may be based on unconservative loads. At the time of EDS's contract, TVA did not recognize that these load increases could have an adverse impact on subsequent support designs and therefore did not require that EDS tabulate these loads on the affected support drawings.

Safe lications Piping supports being based on unconservative design loads could fail during a seismic event. Failure of the supgorts could lead to pipe break and subsequent reduced coolant to the core which could adversely affect the safety of the plant.

Corrective Action TVA is ~ring the load values shown on the individual pipe supgort drawings to the corresponding loading on the revised EDS load tables.

Drawings which have load discrepancies are being evaluated on a case-by-case basis to determine if supports are adequate as designed or if redesign is necessary. The canplete evaluation and rework of supgorts, if required, will be completed, if possible, for Sequoyah before fuel loading. Any required rework not accomplished by fuel loading will be evaluated on a case-by-case basis.

I

,t I