ML20028E354

Forwards Response to Judge Morris 821222 Question Re Deviation of Stress Rule Index Error Bands in Resolution Agreement on Matls Cracking (Suffolk County Contention 24). Certificate of Svc Encl

ML20028E354
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	01/17/1983
From:	Irwin D HUNTON & WILLIAMS, LONG ISLAND LIGHTING CO.
To:	Brenner L, Carpenter J, Morris P Atomic Safety and Licensing Board Panel
References
ISSUANCES-OL, NUDOCS 8301210257
Download: ML20028E354 (6)

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ip H u xTox & WILLI AMG 207 East MAsN srmcc7 P. o. Box ts35. { C' Ricnxown, Vrnotxx.A 23212

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Lawrence Brenner, Esq. Dr. Peter A. Morris Adniinistrative Judge Admin'istrative Judge Atomic Safety and Licensing Atcmic Safety and Licensing Board Panel Board Panel U.S. Nuclear Regulatory Commission U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Washington, D.C. 20555 Dr. James H. Carpenter Administrative Judge Atomic Safety and Licensing Board Panel U.S. Nrclear Regulsatory Commission Washington, D.C. 20555 Long Island Lighting Company (Shorcham): Docket No. 50-322(OL)

Materials Cracking (SC-24)

Gentlemen:

The attached response, in which experts for LILCO, Suffolk County and the NRC Staff have concurred, attempts to i

respond to Dr. Morris' question, as clarified an December 22, 1982, concerning the derivation of Stress Rule I:,dex error bands in the Resolution Agreement on Materials Cracking (SC-24). That Agreement is presently pending before the Board.

Sincerely yours

. W Donald P.' Irwin i

91/867

Enclosure:

" SRI Error Band Derivation" cc w/ enclosure: Attached Service List 0301210257))@h7 22 PDst ADOCK 9 PDR O

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7 SRI ERROR BAND DERIVATION

-- Statements on December 22, 1982 by Dr. Morris (Tr.

17511-13, 17,516) and Dr. Carpenter (Tr. 17,513-14) evinced their dissatisfaction with the written answer presented by the parties to Dr. Morris' question with respect to how error bands involved.in Stress Rule Index calculations under the Resolution Agreement on SC Contention 24 (Cracking of Materials) would be derived. That answer had been set out in a December 17, 1982 letter from Donald P. Irwin to the members of the Board. Dr.

Morris stated his concern that the verbal formula used "could be terribly restrictive or it could have no meaning whatsoever" (Tr. 17,512) and that with a new method such as the SRI, the Board felt that it needed to understand better how it would be implemented (Tr. 17,516). Dr. Morris' observation was echoed by Dr. Carpenter (Tr. 17,513-14). Dr. Morris' original ques-tion had been stimulated by a statement in the Resolution Agreement, at 9:

The SRI acceptance criteria will require that the welds' SRI must be less than 1.0 assuming the most conservative use of the error bands.

The parties misinterpreted the original question by Dr. Morris and responded primarily with respect to the application of error bands.

l The parties undertake this further answer to Dr.

l Morris' question as it relates to derivation of error bands in the SRI calculation:

1. The exact calculational method for development of error bands has not yet been determined. However, the parties do believe that the process is manageable.and that the uncertainties are not such as to make the calculations meaningless. The basis for this belief is set forth below.

2. The general methodology for GE SRI calculation has been widely applied and is well understood. In 1978, for ex-ample, SRI's were calculated for a significant number of welds "

(approximately 60) in the recirculating water system at Shoreham.

3. The SRI is just one of a number of criteria applied in determining which of the 120 welds in the Shoreham recirculating water system to include in the program set out in the Resolution Agreement. In all likelihood, this criterion will be critical to the clarification of no more than about 10 of those welds. The reason is as follows: All but 22 of the 120 recirculating water system welds have received some form of post-weld treatment (24 have received Solution Heat Treatment and 74 have Induction Heat Stress Improvement), thus removing a ____ - - _

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F them from consideration in the settlement program. Additional action for any of the 22 remaining welds requires that the weld -

in question meet additional criteria, namely: diameter greater than 4", inspectability less than 90%, and SRI equal to or greater than 1.0. LILCO has already determined that the number of welds remaining potentially eligible for further evaluation after application of the size and inspectability tests is ap-proximately 10.

4. SRI calculations are performed for individual welds by GE. The calculation typically involves about 8 primary terms (see Attachment 1). The values for each term are unique to each calculation and cannot be ascertained in advance in the abstract, but can be determined on the facts of each weld whose SRI is being calculated. It ic proposed to determine, upon eMamination of each weld, the range of uncertainty associated with each of its terms, and to carry the most unfavorable value within that range through the calculation. Although the parties are not aware of any previous derivations of error bands surrounding SRI calculations, they do not believe this calculation to be subject to unacceptable levels of uncertainty, Of the terms set out in the calculation on Attachment 1, for instance, the factor (Residual) is believed subject to some uncertainty. The range of variaticn for the other defined f actors in the equation either is a function of the specific facts of the weld or can be determined by reference to equations in the ASME Code. In either case, it is believed to be relatively small.

Thus, the uncertainties associated with any given SRI calculation cannot be specified in advance. However, it is believed by the parties, on the basis of experience with these calculations, that the proposed use of these uncertainties will not affect the validity of the SRI calculations to be per-formed. Finally, even if the SRI calculations, as performed,

[ obligated LILCO to take remedial steps as to every weld for

! which the SRI was critical to the screening process, the number of welds potentially affected is a small set. LILCO has recog-nized from the outset that use of the error band could introduce some additional conservatism into the SRI calcula-tion, but felt (and feels) that this potential conservatism would not unacceptably af fect the impleinentation of the Resolution Agreement.

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1 6.5 SINERA! ELECTR!C_Dp10h $ TRESS RULE l

I General Electric has establisted a criterion that identifies thcse stresses signiff-It

.. cent to IGSCC and establishes accropriate procedures for cs1culating these stresses.

() Table 6.3 describes l

wocid also 91 ace limits on the stresses so tnat IGSCC would ret occur. a the Design Stress ble. .

TABLE 6.3. Genere! Electrk Design Sees F.We (Source: 6.1)

Pmmine: stres corrosion can be sworded H semnes are

. snairmained below CJ% oNast yield samt tele: Pg + Pg

• Q

• F * (R6h

• 5y Sy

• c.002 E J Dd"dtio"E Pu + Pg

• Pnmery membrane and bendng . . . . . . . . . ... ..

. . . . m .

ly = A5ME code 0.2% yield stms at appbcable semproture Q = Secondary arous (includes abermah rL Peaksms t

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[ = A$Mt code slastic rroddus at ,

applicable temperature (teddua!) = Sum of at sources of residual

' suess (includig weld resideal a stren and stren resuhing from

< compeanive transiene)

The Design Stress Rule might be used for in-service inspection of welcs that, from a stress standpoint, wowid be susceptible.to IG5CC. It might also be used to assess the potential benefit for rethods of reducir$ stresses at welds; e.g., the heat-sink welding r--hnique to reduce or elininete ter.sil'e residual welding stresses on the inside surface notr the weld. ,

tence and laboratory data does not provide cowinc-Araflable inferration on field exp ing evidence that satisfying the Design Stress Aule will necessarily assure that IG5C not occur.

Further, Sherwood (6.1) points out that even for locations with the aszimue incidents of cracting (Design Stress Rule Index between 1.8 and 1.9), only 15% of the weld Accordingly, even if the Design Stress Rule is not satisfied IGSCC have exhibited 1GSCC.

will not necessarily occur. f4 wever. even if only cualitative in nature, the Design Stress

' Rule concept determines the piping or safe-end locations that could have a high potential i for 1GSCC.

l 6.6 Ca C U5!0'l3

1. Piping systeis in SW.s are corslex structures containing tesy wit.s. Frm a stress Piping design codes analysis standpoint, each weld is 1tself a conples structure.

I provide up;er limits to calculated operation stresses but, because tFose stress bounds exceed the material yisid strength, the code stress limits are not appropriste 1

(a) tiltanabe (6.6) gives rtre dettiled infor3ation on how the Design Stetss Rule is bein med bs enua, outrie...-

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.Y LILCO, January 17, 1983 CERTIFICATE OF SERVICE In the Matter of LONG ISLAND LIGHTING COMPANY (Shoreham Nuclear Power Station, Unit 1)

Docket No. 50-322 (OL)

I hereby certify that copies of the attached letter from Donald P. Irwin to the members of the Atomic Safety and Licensing Board dated January 17, IsB3 and entitled " Materials Cracking (SC-24)" were served this date upon the following by first-class mail, postage prepaid.

Lawrence Brenner, Esq. Secretary of the Commission Administrstive Judge U.S. Nuclear Regulatory Atomic Safety and Licensing Commission Board Panel Washington, D.C. 20555 U.S. Nuclear Regulatory Commission Atomic Safety and Licensing

Washington, D.C. 20555 Appeal Board Panel U.S. Nuclear Regulatory Dr. Peter A. Morris Commission Administrative Judge Washington, D.C.

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20555 l Atomic Safety and Licensing l Board Panel Atomic Safety and Licensing l U.S. Nuclear Regulatory Board Panel l Commission U.S. Nuclear Regulatory l Washington, D.C. 20555 Commission Washington, D.C. 20555 Dr. James H. Carpenter Administrative Judge - Daniel F. Brown, Esq.

l Atomic Safety and Licensing Attorney-l Board Panel Atomic Safety and Licensing l U.S. Nuclear Regulatory Board Panel Commission U.S. Nuclear Regulatory Washington, D.C. 20555 Commission Washington, D.C. 20555 -

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3 . ',

' jr Bernard M. Bordenick, Esq. David J. Gilmartin, Esq. -

David A. Repka, Esq. Attn: Patricia A. Dempsey, Esq.

U.S. Nuclear Regulatory County Attorney Commission Suffolk County Department of Law Washington, D.C. 20555 Veterans Memorial Highway Hauppauge, New York 11787 Herbert H. Brown, Esq. Stephen B. Latham, Esq.

Lawrence Coe Lanpher, Esq. Twomey, Latham & Shea Karla J. Letsche, Esq. 33 West Second Street Kirkpatrick, Lockhart, Hill, P. O. Box 398 Christopher & Phillips Riverhead, New York 11901 8th Floor 1900 M Street, N.W. Ralph Shapiro, Esq.

Washington, D.C. 20036 Cammer and Shapiro, P.C.

9 East 40th Street Mr. Marc W. Goldsmith New York, New York 10016 Energy Research Group 4001 Totten Pond Road Howard L. Blau, Esq.

Waltham, Massachusetts 02154 217 Newbridge Road Hicksville, New York 11801 MHB Technical Associates 1723 Hamilton Avenue Matthew J. Kelly, $sq.

Suite K State of New York San Jose, California 95125 Department of Public Service Three Empire State Plaza Mr. Jay Dunkleberger Albany, New York 12223 New York State Energy Office Agency Building 2 Empire State Plaza Albany, New York 12223 U2/ P;l -

Donald P. Irwin I

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.n i Hunton & Willitms l 707 East Main Street i P.O. Box 1535 23212 Richmond, Virginia DATED: January 17, 1982 l

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