ML20202E048

Summary of 980508 Conference Call with NEI Re Clarification of Priority 1 Generic License Renewal Issues on Aging Mgt Containments (ASME Section XI & Subsections IWE & Iwl)

ML20202E048
Person / Time
Issue date:	01/28/1999
From:	Fred Bower NRC (Affiliation Not Assigned)
To:	Charemagne Grimes NRC (Affiliation Not Assigned)
References
NUDOCS 9902020219
Download: ML20202E048 (14)

Text

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January 28, 1999 NOTE TO:

Christopher 1. Grimes, Director License Renewal Project Directorate Division of Reactor Program Management THRU:

P. T. Kuo, Chief Engineering Section.

License Renewal Project Directorate Division of Reactor Program Management FROM:

Fred L. Bower, Mechanical Engineer

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Engineering Section License Renewal Project Directorate Division of Reactor Program Management

SUMMARY

OF CONFERENCE CALL WITH NUCLEAR ENERGY INSTITUTE REGARDING CLARIFICATION OF PRIORITY 1 GENERIC LICENSE RENEWAL ISSUES ON AGING MANAGEMENT OF CONTAINMENTS (ASME SECTION XI, SUBSECTIONS IWE AND IWL)

By letter dated May 8,1998, the Nuclear Energy Institute (NEI) provided the NRC staff with comments on the Working Draft Standard Review Plan for License Renewal (SRP-LR). Several comments were related to existing ASME Code Section XI, Subsection lWE and Subsection IWL programs for inservice inspection of PWR and BWR containment structures. By letter dated November 4,1998, NEl provided supplemental comments to the IWEllWL issues that were initially raised in the May 8,1998, letter. By letter dated December 14,1998, NEl provided a reference table linking the information in their May 8,1998, and November 4,1998, letters.

The staff reviewed the NEl comments provided by the May 8, November 4, and December 14, 1998, letters and drafted a consolidated description of generic license renewal issues on aging management of containments. Thea list is attached as Attachment 1. On January 8,1999, the

' staff transmitted a facsimile of Attachment 1 to NEl for their review.

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On January 25,1999, at the request of the staff, the staff (Fred Bower, DRPM/PDLR; and Sam j

Lee,' DRPM/PDLR) had a conference call with NEl (Doug Walters, NEl; John Carey, EPRl; and Bob Nickell, EPRI) to discuss and further clarify the issues in Attachment 1. At the conclusion of -

the telephone conference, all the participants agreed to following revisions to Attachment 1:

Generic License Renewal issue 98-0048.

• Elevated Temsei-iore of Prestressina Tendons" The revised title was acceptable. NEl and EPRI requested a revision to include a reference to the applicable SRP-LR pages, 3.3-12 and 3.4-15, in the background section.

Genenc License Ren swal issue 98-0049. "Anina Management of inaccessible Areas of Containments" The revised title was acceptable. NEl and EPRI requested a revision to include a reference to the applicable SRP-LR pages,3.3-10 and 3.4-19, in the background section.

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Generic License Renewal lasue 98-0050 "lWE/lWL to include Basemat" NEl and EPRI requested deleting the first paragraph of the background section since their l

comment was specific to BWRs. It was also agreed that the second paragraph under

• Background" should be revised to reflect that the draft SRP identifies concrete containment as part of the pressure boundary in accordance with the industry report. Because this issue is specific to BWRs, all participants agree that the priority of the item should be lowered to a j

priority 3. EPRI also agreed to contact industry representatives that commented on this issue to 1

obtain and provide additional clarification.

Generic License Renewal Issue 98-0051. "lWEllWF: Jurisdiction" l

The revised title was acceptable. Because this issue is specific to BWRs, all participants agree that the priority of the item should be lowered to a priority 3. EPRI also agreed to contact industry representatives that commented on this issue to obtain and provide additional clarification.

Generic License Renewal Issue 98-0052. "lWEllWF. Operatina Experience Reauirements" All participants agree that no revision or further clarification was needed for this item. EPRI and NEl did note that little operating experience has been gained in this area since 10 CFR 50.55a j

and the code were recently changed.

I Generic License Renewal issue 98-0046. "Insoection of Containment Welds and Bellows" l

i The revised title was acceptable. EPRI and NEl requested that the last sentence of the "NEl l

Comments" should be revised to read, "It is our position that the current requirements of 10 CFR 50.55a are adequate for both the current and renewal terms, including Exam Categories E-B and E-F."

Generic License Renewal issue 99-new. "Fatioue of Penetration Bellows" l

'(Top of Page 5 of Attachment 1)

All participants agree that no new item needed to be created for this issue because there is agreement that fatigue of penetration bellows is a time-limited aging analysis.

Generic License Renewal Issue 98-0040. " Freeze-Thaw Damaoe in Concrete Containment Structures" EPRI and NEl requested that a sentence should be added to the end of the "NEl Comments" to read,"This position provides criteria for determination of potential significance of freeze-thaw damage."

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Generic License Renewal issue 98-0041. " Alkali-Aaoreaate Reactions in Concrete Containment f

Structures" EPRI and NEl requested that a sentence should be added to the end of the "NEl Comments" to read, "This position provides criteria for determination of potential significance of alkali-aggregate reactions in concrete containment structures."

Generic License Renewal issue 98-0042. " Differential Settlement of PWR Containments and l

Class 1 Structures" EPRI and NEl requested that a sentence should be added to the end of the "NEl Comments" to read, "This position provides criteria for determination of potential significance of differential settlement of PWR conta!nments and Class 1 structures."

t Generic License Renewal issue 98-0043. " Reinforcement Corrosion in PWR Containmen_tg."

EPRI and NEl requested that a sentence should be added to the end of the "NEl Comments to read, "This position provides criteria for determination of potential significance of reinforcement corrosion in PWR containments."

Generic License Renewal issue 98-0084. "Aaina Review of Airlocks and Eauioment Hatches" All participants agree that this item should be deleted since the issue will be addressed by the resolution of Generic License Renewal issue 98-0012 on consumables.

Generic License Renewal Issue 99-new. " Structure Scooina in NUREG-1611" (Bottom of Page 7 of Attachment 1)

All participants agree that no new item needed to be created for this issue. NEl was providing an observation on NUREG-1611. NEl did not identify an issue or comment applicable to the SRP-LR.

Generic License Renewal Issue 99-new. " Structure Scooina in NUREG-1611" (Top of Page 8 of Attachment 1)

All participants agree that this issue should be categorized as Priority 3. NEl and EPRI requested a revision to include a reference to the applicable SRP-LR pages,3.3-56 and 3.4-71, in the background section.

Generic License Renewal issue 99-new.

• Erosion of Porous Containment Sub-foundation" (Bottom of Page 8 of Attachment 1)

All participants agree that this issue should be categorized as Priority 3.

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3 At the conclus;0n of the conference call. NEl agreed to prov de a:itionc! c!2r:1. at.cn on issues i

98-0050 and 95 0051 in about a wsek. The sta-! plans on transm:ttin:: a ierer to i E! witn ine revised descr:ptions ci the Generi: Licente henewal issues on aging management of containments.

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DP AFT,1/S/99 D _ S"w R mTloN rr e_r.. r.in.. r : r F. N O:.. P.._N _".,'; ' I S C. In c D N

/ G!N2 W h AGETENT OF CON 14:NMENTS (SUO. 'Cf!:CE iWE AND l'/.i C? ASVE EECT!ON XO Generic License Renewei 'ssue 98-CCe "E!cvcted Ts.mocratu e e' Prestrestca Tencens-1 Revised tit!s)

Prict:tv 1 Backcround Pages 18 and SS c' NUM EG-1611 indi; ate inri efeeated temperatures may increau the prestress loss in contc;nment tendons Thus cn cou$ cant snouic augment the tencr.:n su'veillance program ic mciuce a:articr5 Ic-cons seiecte: based en their sun exccsure or prommity to hct penctrations inis inicrmat.cn is in:crporateo into ine craft stancsrc rem; p!am for hcense reneveal.

RE' Cemn ents l

The selection of the 40'c prestressmg tencon sample. in accordance with IWL-2E21. is sucocsed to te random The NRC sic'f hss tne cot n c r edity:np P.egulatory Guica 5 35 to provice geacn;e on the selection ct tencens to inciace one tenecn from such regions cf t% co tam. menti potantia!!y exposed to nigher tcmpec.:ure SCentng acait.on.? ten 00ns b6 /end tne C-sampte size need nct be the ONy cpim in a: Scn :f tne argJr em inct a reiat vek s':gm incresse in picstressing tendon ser/;ct tcmr.a ature (from 200 to 02C) cauhed by exc;. are to :,. nhgnicould acuble the loss cf crestress is mi the NRC sist snca:: not'y inc auptctnete ASE Code Sect;cn XI bodies te conocer c1cag a pcrapreh to l'N_2521 te rc T.;t tenaen se!t:::on te te cased in part, on environmenta! con 0:tions, Tn.s sncu'd n0! be Ec:t.!y a hCense renevsal Consideration.

-Gcrer<c Lice,se :ene rai !ssue 98-0020 "Ac~ne ManaaeT=-t cf Inaccessit'e areas of Con?smmentL" (he /: sed Wy Pr:arity 1 Scocound NUF.EG-1611 endestcs that en crdicant shc/d manage the potent 2' aging e"ect nf containmc t sructures in ir.accessoie areas venen ce".d;t:cns in accesstie areas r q nct inc.cate the cresence at or rewtt in ocgracadon to se:.n inaccessde ari.as. Tnis intcrmationis incorporatea into tne drah stancard review pian for ti:ense rcrienal Attachrnent 1 1

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Nr4 Comments Fc:(1) one-:%e insperon for license rcrewa!. (2) leach:ng of calcium hydtcv de (3) ag;*essive chemical attack, (4', corrosi0n cf structural stee' and hners, and (5; corrosicn ci emcecced retnforcing steel. NUREG-W11 cnd the werk:ng dra't standctd resew p:an for Lcense renewa! go we4 beyona the adcitional reau:rements of the 10 CCR 50.55a ru!emekng rc ommend:ng au;;mented insce: tion of ins;tess!b!e a<eas even when no evidence ex:sts in an actes sitie area.

that pctential degradaten has taken place.

The PWR Containment industry Repe t identf,ed enrrosion of be:owtrade concrete and steet structures causec by aggressive g"ounc water as a sign:ficam ag;ng e:1ect for wh ch current penodic inscr/ce inspmon prop ams cculd not be shown to De adecJtte. A S rMr cccclusien i

was reachea in tne EWR Containment incustry Repor Both incustry Repons suppme: pter,t-scecif:: mccrams to soaress tne :: sue, sta tin.a w;;n a determ:nscon of c_rounc w de: che nisry r

4 tripanicu:ar tne thresnclos for agg'ess:ve acidity (pH<5.5), entonos centen: p50'. cpm) anc j

su!! ate centent (>1500 com). For belcw-grace concrete and stee! con:a nmen; st'u::urcs that are not in c: rect contact w!:n agg'esshc ground wa:cr. no furtner action was ceemeo ic be recaired. Wnon agaressive grounc wa:Er is in c.rtct contact w,in De!cy grade concrote or stes t con a:nment strucitccc a number o' anerna:! vet were suggestec inctuding the inst a:!on of a barner s)sicm ie.g, a water.orcof mentraney, redJong the wa cr tabte te oreirm cirect centact, or sampi: 7 intreet cns of :naccesstic reg ons ocow ine water tab:e in nc case dd either of the locastry Rcpens suggest augmentao inspe tion of inaccess.bie regirns wncn no ev ence is present in access; Die areas that v;caid inda.cte potental ccgra:st;cn.

No rast'ficrSon far the r.upmentaten coverec n tnis iten cou!d bc found either in NURE3-16M or in tne werMng crzn Ranca o rei.ew o'an tar i.censc renev.al which imo,cments tne NJREG-.

1011 cen <us On Tntreic E :is our e cw th.* :ne guicance r the industry Moor;s is acequa:e anc inspset: ens are nct requitec un:ess spe'c ed in the Industry kep n. or in 10 CFR 50 5Ea.

Generi: License Renewa! Issue 98 0050 'TNEJNL to hetude Essema:"

Pr:cr;ty 1 j

BES70gLd Sec::cn 3 3 cf the d'a+1 standard review p'cn +ct I:censs renewa: rnd; etes th:t the EFccts cf freeze-f:aw on PWF contmnments wou!d te accquately managed by ExemocLon Ca*.cgory L-A i

of Subsecton PNL cf Section XI of the ASMC Cocie The anecte: conta:nnien: structure componen:s listeo incicde tne concrete basemat.

In addiion. although Section 3 4 cf tne drafi standard review plan for license rer'ewa!in5cr.es i

tnatit does not add ess c+1a:n basemais,it a aressesine p;:entra! ag.ng ef:ects cf tn6 su>

foundation layers beluw ine casemats.

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net Co rmcis Ccmment No. 23 in the NErs May 8,19EB, letter states that 'The NRC has expcaded tne 5,;c:>a of IWL to inc!ude tne sub-founcation layers in the sconc of contamment te p. the S NR f/ 3rk li centainment basematt However. cn pEge E L1. the draft standard review pb for I:ce s,e renewal states that The centainment structure com;onents descnbed in tnis secten cots no*

include the Reactor Eu3 ding ctructures an baumct: cf Mark I and Mark il stee: contamment because they c0 n si form a ponion o' the cent.nment pressure boundary: the c:aphragm tocrs and suppOn colum":s of Mark 11 conta:nments' or the cryweli anc weir wah of Mark lli i

containments' them are Class ! structures and are d: Cutsed in Section 3.9 cf thic W " The werkmc crcP stancrd review plan acpears to nave fc!!Dwec the scopc cf coverc;= 9'ven an tre BWR Conta,nment industry Report Genene License Renewc!!ssue 95051 -Ini L*.'r Jm d; tion' (Revised titte) 1 Pr'ori+v 1 i

Eackcround i

Fage 46 cf NUREG-1M1 i"dicates that wear c' EVG contanment structures and sucpo".s wcufd be a0eauster,' racnagec by Sucsect:ons iWE an:i P//F of Section X1 ct !!:e AEME C ce.

Pages 33 ana 34 cf NUPEG-1611 mc; cates mr: c rr( s:cn of BWR cor a mert structures and i

sucpcNE wou c :.e adwaa'ely managed by Sa.. ;t ca i/.E CW. Inis micrrnahon is t

incorporated :nto tne c c't standarc review pian r:,r nense renu. val.

1 NE1 Comments Commert No 43 in the NEfs May 6 19EB ki.wr is a caeston abou* the ) msc: tic ef A%fE Section M, Subsect:ent l Al ve%us inF. HD.wver. Sr.;: ens 3 4.ll.C 6 and 3 4 th C 6 ct the c* aft stancard re/:ew o'an fcr license receu: cs i cut f xaminstcq Cater F t-as c prcgram aceouate to manaae tne eFects of to:Rup on cenam E'NR cnnta6 ment sue:.c. structures, su:b as vent system sucpons fcr Ma-L i steel conanmirS Excmnatien Catgar3 ;-A should a:so ce etted as an acecus e proc am fc: manag ng ine ene:.ts cf loss of mattna: (ccrrcs.cn) sra Se: tion 3.4.it.C.10 anc 2, 4.ili.C 10.

[dnric License Renevra'Iseue C50M2 *lW nnt Operatm:0 Evrew:e ro.,re ents-F: arb/1 Barkeroend Sections 3.3 and 3 4 of the draft stanca d review cito fer license renewal ad:cate that an acplicant sh0uld aiscuss operaung expenence cf ine;r IWDPvL containment :ncerv.ce inspec%m program.

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t NE! Comments Tne draft standard review plan for license renewal includes a recu:remer.. 'or the applicant to l

I-oiscuss the operating excenence witn vancus Sut'section WGM inspections, including any corrcctrse actiers from tnese inspections that may have crc Wded fEr Ocack to the plant owner, end that may nave led to e:ther inspection procram enhcnccmnts or new inspections programs.

Such cn aoditional reauirement, over and above a deterrnmanen ny ine applicant that Subsection l

IWE/lWL inspections manage the effects cf c;;mg through the h:ense rmewal term, seems unwarrantei

_Ganeric License Renewa' Issue 96-00451n:ri: tion of Comcinms,t Welds and Bellows" (Revised t,tle)

Pricrity 2 Backcround Page 3 of NUREG-1611 indicates that an app'icant shodd nc -for~ inerections of containment pressure retaining welos in accorcance eth Examinate: Siq.ne: E-E and E-F of Section XI of tne ASME Code. In addition, NJREG-1W mc tmcs r 2 cn :-poaccnt snould perform augmemed inspections of containment pensnt en bru n to mc.op: pottntial cracking. This information is incorporated into the draft stancerc revie.v pin for it:ensc renewal.

NEl Comments l

This item derives frrm Information Nctice C2-20. "Inadcuur.*c '.cce' Leak Rate Testing," dated March 23.1991 baned on an incident at the Quad C$c3 S:smn Ur 't 1. curing the conduct of a l

Type B !ccalleak rate test (LLRT) on a conta nment cererv en tseer Excessive air leakage from the tenctration was sitributed to ~cra:xs icentf ed m P.e test. ~ t:n me cracking was not

. charortenzea The Contatnment industry Report recrr vee semc pcts-t:al for stress corrosion cractung of tne dissimitar metal we!d ontween tne sic:nitse seet tch s assembly and the l'

- caroon steel containment pencitation s!seve, when repeserts a creviccd geometry. However,

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ine attacnmerd cesign minimizes operattna! s%sses trem thermai cycnng or pressure testing, l

and tne environment is net agg'essive with re:ccci to ch'ences. saffates or acidity. For those few cues whcre plant-specific conditions cre ra:n thet ins t*ndm aces not apply, the surface examinations of Examinction Cstegory E.F (c'ercure-rettining d nimder metal welds) and the visual examinadons of Examinstion Category E.r> (Append > J lent tasto are more than adequr.v. to detect the cracking, and no cupmented inspe tions cre nece ssary. This item also represe is an area of c:sagreement by the I AC sta" m t% L' cense: Renawal Project Directorate w:th the 10 CFR 50.55a ruiemaking, where enminat ens cf c.ssemt rnetal welds, as required i

by Subsection IWE. were determined to have lin ^ IaiMy bene f:t Cna v ert therefore determined to be optional, it is our pcsit.on that the current recaircme.ts of 10 CFR 50.55a are adequate for both the current and renewal terms.

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Generic License Renewalissue 99-new. *Fatiaue of Penetration Bellows" Priority 2(?)

Backaround Pages 20 and 40 of NUREG-1611 indicate that containment penetration sleeves and bellows are designed to Section lit of the ASME Code, which requires a fatigue analysis based on an assumed number of cycles. This fatigue analysis is a " time-limited aging analysis" and must be evaluated in accordance with the license renewal rule, M CFR 54.21(c) to ensure that the effects of aging on the intended functions will be adeque. sly managed for the period of extended operation. This information is incorporated into the draft standard review plan for license renewal.

NEl Comments it is not clear why this itemis listed in NUREG-1611, since the effects of fatigue of containment penetration bellows and penetration sleeves, in particular for hot penetrations, were found to be potentially significant in the Containment Industry Reports, requiring either periodic inservice inspections or fatigue re-evaluation (e.g., time-limited aging analysis), or both. This does not seem to be an augmented requirement since fatigue of metal components is a time-limited aging analysis. It should be noted that fatigue of metal components is Generic License Renewal issue 98-0028.

Generic License Renewal Issue 98-0040. " Freeze-Thaw Damaae in Concrete Containment Structures" i

Priority 3 I

Backaround NUREG-1611 and the draft standard review plan for license renewal indicate that acceptable methods for managing the effects of freeze-thaw in concrete containment structures are Subsection IWL of Section XI of the ASME Code.

NEl Comments The industry technical position and its justification for freeze-thaw are provided in EPRI TR-107521.

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1 Generic License Renewal Issue 98-0041. " Alkali-Aaarecate Reactions in Concrete Containment j

Structures" Priority 3 '

Backaround i

NUREG-1611 and the draft standard review plan for license renewal indicate that acceptable methods for managing the effects of reaction with aggregates are Subsection IWL of Section XI of the ASME Code and the requirements in 10 CFR 50.55a.

NEl Comments The industry technical position and its justification for alkali-aggregate reactions in concrete containment structures are provided in EPRI TR-107521.

Generic License Renewal issue 98-0042. " Differential Settlement of PWR Containments and Class i Structures" Priority 3 Eackaround NUREG-1611 and the draft standard review plan for license renewalindicate that acceptable methods for managing the effects of settlement are settlement monitoring during construction and continued monitoring during operation for sites with soft soil and/or significant changes in ground water conditions.

NEl Comments The industry technical position and its justification for differential settlement of PWR containment and Class I structures are provided in EPRI TR-107521.

Generic License Renewal Issue 98-0043. " Reinforcement Corrosion in PWR Containments" Priority 3 Backaround NUREG-1611 and the draft standard review plan for license renewal indicate that acceptable methods for managing the effects of reinforcement corrosion in PWR containments are Subsection IWL of Section XI of the ASME Code and the requirements of 10 CFR 50.55a. In addition, the management of inaccessible areas of embedded steal should be evaluated.

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9 NEl Comments The industry technical position and its justification for reinforcement corrosion in PWR containments are provided in EPRI TR-107521.

Generic License Renewal Issue 98-0084. "Aoina Review of Airlocks and Eauioment Hatches"-

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(Revised title) i Priority 3 Backaround NUREG-1611 indicates that mechanical wear of pressure retaining components, including airlocks and equipment batches, should be adequately managed by containment inservice inspections in accordance with Subsection lWE of Section XI of the ASME Code. This information is incorporated into the draft standard review plan for license renewal.

NEl Comments l

,On pages 26 and 46 of NUREG-1611, it is recommended that Subsections IWEAWL be used as the basis for demonstrating that the effects of mechanical wear on PWR and BWR containment pressure retaining components are managed during the license renewal term. Those components subject to relative sliding or rotational motion, such as airlock and equipment hatch seals and gaskets, are cited as specific examples. However, such items are replaceable and are not within the scope of the license renewal evaluation. Therefore, consideration of the effectiveness of maintenance activities related to replaceable items should be eliminated from NUREG-1611.

Generic License Renewal Issue 99-new. " Structure Scooina in NUREG-1611" Priority 3(?)

Backaround

. NUREG-1611 discusses aging management of nuclear power plant containments for license renewal. Page 2 of NUREG-1611 indicates that an applicant needs to perform evaluations to meet specific requirements contained in Part 54, the license renewal rule, such as 10 CFR 54.4 for scoping and intended function, and 10 CFR 54.21 for time-limited aging analyses regarding 7 the containments.

NEl Comments This item pertains to procedural requirements contained in the license renewal rule, and does not include information on evaluations and inspections. We do not understand why this item is included in NUREG-1611.

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_Ger,eric License Renewal Issue 99-new. " Ultrasonic inspection Qualifications for Containments" i

Priority 3(?)

Backoround l

F Sge 2 of NUREG-1611 indicates that ASME Section XI, Appendices Vil and Vill should be implemented when ultrasonic examinations are utilized for the inspection of containments. This I

information is incorporated into the draft standard review plan for license renewal.

NEl Comments This additional requirement does not seem to be applicable, and it is not clear why such a requirement is being imposed. Thi only volumetric examinations required Dy either Subsection IWE or IWL are those of Examination Category E-C for determining the wall thickness of steel containment structures. The purpose of the personnel qualifications of Appendix Vil and the performance demonstrations of Appendix Vlli is to detect and size flaws in components for which standard flat-bottom hole calibration blocks are not representativo, especially in situations where straight-beam methods could be unreliable. Measuring ultrasonic wave propagation across wall thickness is completely unrelated to these issues. The supplemental examinations of IWE-3200 could trigger surface examinations to size flaw lengths, but are not likely to trigger volumetric examination. Even if supplemental volumetric examination were to be considered, in order to justify continued operation without repair, the alternative of a containment shell repair in accordance with IWA-4150 would be preferable, especially since no calibration specimen satisfying Appendix Vill for containment shells is available.

Generic License Renewal Issue 99-new. " Erosion of Porous Containment Sub-foundation" Priority 3(?)

Backoround NUREG-1611 indicates that an applicant should evaluate erosion of cement for porous concrete if sub-foundation layers of porous concrete are used in the construction of containment concrete basemat with the presence of underground water. This information is incorporated into the draft standard review plan for license renewal.

NEl Comments The Containment industry Reports found that the effects from leaching of calcium hydroxide were not significant for concrete containment structures unless such structures were exposed to flowing water and, if exposed to flowing water, could not be shown to be constructed of dense, well-cured concrete. Porous concrete exposed to flowing water would fallinto the category such that the effects of leaching could be potentially significant. Information Notices No.96-145, dated October 17,1996; 97-11, dated March 21,1997; and 98-26, dated July 24,1998; have addressed this concern for nine U. S. nuclear plants (Beaver Valley Units 1 and 2, Fitzpatrick, 8

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Haddam Neck, North Anna Units 1 and 2, Surry Units 1 and 2, and Perry), following the incidence of reported erosion of the containment foundation basemat at the Millstone 3 Nuclear Power Plant. Information Notice 96-145 stated that there was no safety concem, since the Millstone 3 containment foundation, is founded on rock. Also, the amount of concrete that may have eroded since plant construction is only a small fraction of the total cement weight, and no adverse consequences have wither been observed or predicted.

It is not clear why this relatively minor current plant issue is being called out in NUREG-1611, which will have been addressed by plants looking for evidence of slurry in the drainage below their containment basemats, and for any settlement of the containment basemats. NRC also asked these plants if they have noticed any unusual conditions which may be related to the porous concrete sub-foundation layers and if they are monitoring anything related to the drainage from the porous concrete sub-foundation layers below their containment basemats. The most recent IN 98-26 has indicated that the NRC staff may inspect licensee sub-foundation monitoring and preventive maintenance programs as part of NRC Inspection Procedures IP 62002 and IP 62003. It is our position that this issue only applies to a few plants, and that the current practices l

that the subject plants have implemented are adequate to manage this aging effect for the renewal term.

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