ML20197F637

Discusses IE Unresolved Item 80-12-01 Re Multiple Cadweld Splices in Containment Primary Shield Wall.Worst Case Area Should Be Subj to Crack Pattern Mapping for Structural Integrity Test,Per Reg Guide 1.18.W/o Stated Encls

ML20197F637
Person / Time
Site:	Seabrook
Issue date:	07/16/1981
From:	Martin T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:	Baer R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE)
Shared Package
ML20197F642	List: ML20197F637 ML20213G164
References
FOIA-86-756, RTR-REGGD-01.018, RTR-REGGD-1.018 NUDOCS 8109280057
Download: ML20197F637 (22)

Text

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Docket No. 50-443 JUL 161931 MEMORANDUM FOR: Robert L. Baer, Chief, Reactor Engineering Branch, IE FR0M: Thomas T. Martin, Chief, Engineering Inspection Branch

SUBJECT:

SEABROOK UNIT 1 IE UNRESOLVED ITEM N0. 80-12-01 MULTIPLE CADWELD SPLICES IN CONTAINMENT PRIMARY SHIELD WALL This memorandum confirms a telephone conversation between E. Gallagher and A. A. Varela relative to the enclosed technical evaluation in answer to Seabrook unresolved item number 80-12-01.

United Engineers and Constructors (UE&C), the AE on the Seabrook project, has responded to a licensee request to answer Region I concerns regarding potential excess strain accumulation across more than two cadweld rebar splices on a single number 18 rebar where engineering drawings call for only one splice. In IE Report No. 50-443/80-12, paragraph 2 (enclosed) the inspector expressed his concern that due to over conservatism in AE requirements on cadweld splice end void measurements, a high reject rate resulted in multiple replacement splices. IE

! Report No. 81-02, paragraph 3 (enclosed) identifies that UE&C has established new I

'cadweld end void measurement standards in close agreement with ERICO. However, at that time, UE&C had not provided to the NRC inspector information as to identification and location of existing multiple splices on the same bar in the containment primary shield wall.

We are now in possession of as built drawings showing locations in the containment building primary shi ld wall where more than two cadwelds replaced successive rejects within a full bar_ development length. We have reviewed these drawings and found thatCmultiple_ replacement splices occur at 80 locations. In this number of individual bars, there appears to exist the " worst case" as described on page 2 of the enclosed technical evaluation submitted by UE&C in response to IE unresolved item number 80-12-01 (UE&C memorandum of March 26,1981).

Since this technical evaluation is based on a design analysis that assumes certain values of additional deformation (slip), it is the opinion of the Region I staff that this represents a modification to the facility design.

.We have recorsended that for the structural integrity test, an area representing

'the " worst case" be subjected to crack pattern mapping per Regulatory Guide 1.18.

The licensee has refused to make such a comitment based on the enclosed UE&C evaluation. The licensee emphasizes that no code (ASME III, Division II) requirement has been violated.

CONTACT: A. A. Varela ^

8-488-1267 8 I 8I o'HL%0057 JA *f9

/ F.cbert L. Baer 2 We recomend that this matter be reviewed by your staff and, if they concur with our concern, it be forwarded to NRR for their consideration of the need to impose additional structural integrity test requirements.

h as T art Chief *

. ngineering Inspection Branch .

e ;Endlosures: As stated ,

cc w/ encl:

, G. Arndt, Office of Standards A .C. Certi e,$4bruck RfJ/Ebisf Inifcckt

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. 5 the painting contractor to omit paint from any liner areas with questionable surface conditions or potential defects.

Another inspector observed the following 1Jnit I construction activities:

select soil backfill and compaction for the service water pipes in the area between Units 1 and 2; application of water seal membrane and protective cover below grade on diesel generator and waste process buildings; prepara- .

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, tion preceding concrete for the Primary Auxiliary Building south wall; -

/ .

- containment spray pipe alignment and weld prep in the equipment yault ,

safety injection pump tank weld and -fit-up; containment interior slab at Elev. 25'/co'ncrete preparations; and rebar installation in the containment exterior wall. -

No items of noncompliance were identified; however, one item remains unresolved

. as discussed below:

Aninspectorobservedfourconsecutivecadweld_sjlicesonaverticalouter-Tya Er F18.rebar f or7hrV5Tt I contaisnent bhi1 ding' exM waTi~"ThisW- '

splices were id6nrified Es EuinEer' 170~Rs~an~d were noTid to~'5Ecur between Elev. 4.5' and about 8.5' . Later the inspector was informed by contractor that other similar series of cadweld splices exist in the containment wall vertical and diagonal 7ebaT These were the result of replading a reje_c.t_e.d cadweld splice, when cut out, with two cadweld splices. Upon inspection and rejection of any replacement cadwelds, their successive replacement by two new splices has resulted in situations where a series of cadweld splices now exist where originally only one was required. Th_e_ inspector __reques_ted that the extent and locations where a series of more than two cadweld ,

splices hasten providdd when 'only one was originally d taile~d to be-defined, evaluated, and justified taking into account the acceptable concrete cTack"si'ze'resulting-from p6tential Excess stfaih ac'cumulation across each location .where series.of. splices exist on one reba. . The inspector also question'ed what causes have been attributed to the numerous visual rejections

~

of cadweld splices and what corrective actions have been taken by the licensee to reduce this reject rate. .

l S'ubsequ.ertt_ly. it.was -learned that a UE8C ECA (10/0041.B)._is_to be issued

'cTa'nging c the method by-which cadweld _en'd'WiTinTasu'rements arelakin to b7iiij tlimnne'siLiement techniques in line with,'th's ERICO inten't and avoid the7nn'ecessary conservatism leading to the liigh re'ect j ra'te

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arid multiple-reW aTement spl1ces. ' ~ '

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Pending review by the NRC of the requested justification for acce'ptance of i existing numerous cadweld splices in series without any apparent specified

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limit; NRC eisinination of the new cadweld void measurement techniques; and NRC evaluation of any further licensee corrective action, if justified, this item is unresolved (443/80-12-01).

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(0 pen) rioncompliance (443/80-13-03): Failure to control and document the encineering review and approval of a field initiated design change. The licensee.'s response to the subject fiRC notice of violation was reviewed and interviews were held with QA and engineering personnel. The inspector indicated to the licensee that their response did not adequately address the prograrmatic des'ign ' control aspects of this issue. While the results of an analysis done to justify the acceptability of the specific case were presented, no apparent recognition of the fact that this analysis was done after the ,

fact was documented. Addi.tionally in referencing certain Engineering Change I

A,uthorizations, contradictory information appears to have been provided. . .

! The licensee has committed to the submittal of a revised response to the notice of violation, clarifying their position and the corrective actions being j taken. Pending review and follow-up of this information by the f4RC, this item remains open. _

(0 pen) Unresolved item (443/80-12-01): Justification for multiple cadweld splices in series. The inspector reviewed UESC Engineering Change Authorization

(ECA) ~10/0041C, approved on December 2,1980, which establishes new criteria for the final QC inspection of cadweld sleeve end voids. fiew measurement techniques are established in line with both Erico standards and an intent to change the conservatism of the present system which has led 'to a high cadweld reject rate and multiple replacement splices. Additionally ECA 01/2127C directs.that cadwelds be staggered a minimum of 24" and limits the number of cadweld splices on any single bar to two splices within a full bar

- developtrent length of each cadweld in each direction. The inspector verified .

the adequacy of these changes with regard to both ACI 349 provisions and

, state-of-the-art considerations.

However, no documented information as to the identification and l'ocation of existing multipl'e splices on the same bar was available for review.

. The ' inspector requested that for the worst cases in high tensile stress areas, the acceptance of more than two splices within a full bar developmen't length be evaluated and justified. Pending tiRC review of this information i

and analysis, this item remains open.

I

4. 30CFRSD.55(e) Report Closure On tiovember 6,1979 the licensee telephonically reported to the flRC a significant deficiency under 10CFR50.55(e) with regard to discrepancies in concrete reinforcement drawings. On December 6, a final report, entitled i " Discrepancy in Drawings with Respect to Design Calculation Concrete Reinforcement Requirements for the Control and Diesel Generator Buildings,"

was submitted in fulfillment of 50.55(e) written reporting requirements.

~

At the time the drawing discrepancies were discovered at the UE&C home office l

in Philadelphia, no concrete had been placed at the specific affected locations, although some rebar dowels from previously placed concrete were lacking.

/

MEMORANDUM .

a cowtructrn rc

a. 97h3.00f, Orr ec t: Philadelphia -

,. Power Engineering D ATE: Mareh 26, 1981 .

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dul shizer - E v[ Cor scs: L. S. Nasc1 cento  !

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. i Sun >Ecr: G*lli.lC SKRVICE OF NEW IIAMPSHIRE *

- SEA 11ROGR STATION - SIDI.TIPLE CADVEl,DS -

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, 11N A _ S INGLC REIN!'OHClhG liar I .

I .

At tach d is a technical evaluation of the areas identified in the , ,

survey inf the tinit 1.* hell which den.onstratus that the effect of ,

r.sultiple Codeelds in t h s- contain ni nt shell is i n s t e,ni f i can t . .

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Assistant Chi e f- .  ;*- .

Structural Eogineer i JJi!:mck '

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' PU3CPOSE OF EVAtt1AT104 - .

' f fect of multiple cadwelds (more than two) on the response of

. ' To det aristne the e-

.s the containmpnt undier postu}nted design loading. .

l . e O I -

s ritLD SURVEL -

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Ni feld survey la being- perfurmed to identify the incationn where more th'an two To date t,-

Ca, welds pre lucated on ti ><in;.le b:tr within a h.ir sieve 3upment Acngth.

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survey h'ns been completed for 'the shell of Unit I and the mnt of Unit 2.

The ,-

1 the r e. .

.ainingarlenswJl be revleEcd when the survey is completed.

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ICES 1* .B_EHA.VIOR OF REINFORCING BARS WITH CADVEl.D SPL -

ta have shown that reinforcing bars with mechanical butt splices (Cadwelds)

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exh ibit nonlinear behavior under lund. This is prianarily due to a, lip of the I

! Tests have shown that this A11p can be on 1  !

ren nforcing 'bar within the uplice. .

This ulip will cause a

.' the order o[ 0.040 inchen nt a stress level of 45 Ksi.

A localtred reduction in stif.fncss of a bar with a Cadweld. 1

% t reinforcing bars with niultiple Cndwelds the stif fness tw further reduced.*

GG Fo r Th e ef fect uf this localized reduct ion in stif fness is to slightly "sof ten" b the reinforcing bar(s) with the 1

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th e afiell and to redistribute the forecia :f romr j In the discussion below the reduction .

mu ltiple Cadwelds to other stif fer bars. '

. Inerense in the nearby reinforcing har in shell st il

ness and tin s ut resp..nding .

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,c t 3.ners .ir. ohnen to be inninullleant. *  ;

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- EF FECT Of .M0LTIPl.E CADWF.LI)$ - -

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e ef fect tif cultiple C'.sdwelda is to s}Ightly alter the stiffness and stress  :

should he noted thast quality assurance procedures insure his;h I .

di s t r ibut l etk. It -

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' zen, ii. A. , and Gamble W.L. ,

Strengtl. ar'd' Cracking Characteristics of ACI Beams Journal  :

th Number 34 and Number 16 Bars . spliced with Mechanical Splices.

• D cember 1969,

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1. qtality Cadfeld splices copuble of de'veloping speet tled minimum st rengths.

D e capacity (ultimate ot rength) is not ultered for the case of multiple

• Ca dwelds. however, the load deformation relationship is c. hanged, for a ba'r it. the vicipity of the Cadwelds. .

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. Tr isigniffhantpostulatedloadings in containment design are LOCA (pressure '

• ard tempera [ture) and seismic. Each of these Joac2ngs 2nence a globai type or }

e, "erall response in which large regions of the shell are constrained to re- L.

I s pondasapnit. The presence of the liner (even though it is not relied upon to take loa.d) 1 and the sciemic reinforcing further serve to distribute the load .

o "er a large area minimizing the ef f ect of local changes in stiffness, s  ;

i 45 segmdnt of shell is representative of a region of overall response. The A

r esults et the field survey were reviewed to determine the maximum number of j

r einforcing bars with multiple Cadwelds in a 45o (55 feet) region of the shell I

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s urface for zones equal to the development length of the bar. The " worst case" f

Y esults arq as follows: -

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• M e ridional jReInforcement - 6 bars /55 feet  ;

[Electriedl Penetration- Ares) ,,,,

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H )op Reinforcement - 3 bars /55 feet ,

n S Ismic Reinforcement - B bars /55, feet (Mechanical Perectration Area) '

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I t is assuged that the stress strain behavior of a bar with multiple Cadwelds I

I r an be modIfled by assuming that the additional deformation (slip) can be dig-1 I

cibuted over l a length of bar equal to the thickness of the shell .

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Tae n11p of 0.040 inches at 45 Ksi 1

is equivalent to approximately 0.05" at I -

t bea33nwnhlestre.sn of 0.9 Iy or 54 Ksl (ASr1C Section III Divisica 2 Code).

- T he ef fective modulus of elasticity of a bar with an additional Cadweld can le enmputed.a.s follows:

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T readditiohalstraindur to slip is: ' - .

.' c = "I P . '

wall thickness l'

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U.05 I 'a 12 x 4.5 ,.

- - c - 0.0009 . .

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8 The total w' train at yield for a bar length equal to the wall thickness is:

f * '- '

. c - 0.0009 + 0.9c y $

total .

60

'- . c = 0.0009 x 0.9 30x10 3

. total l '

! c = 0.0027 8 total T,e effectLve r:odulus of einsticity 1s: .

! E = $4

- cffective 0.0027 l .

3 l' = 20 x 10 Kai .-

F.e ffcetive '

I 1hus, ther'e is a 3/3 reduction in stif fness for each additional Cadweld.

. l ecause the postulated design loadings produce overall response, the shell l-

oa'dtng ma'p conservat ively be assupind t u be dist ributed over a regihn of I  : .

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SS feet foy meridinnn3' and hoop forcen and 110 feet for tangential shear, ,

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,ince rer.I'ons of the shell 180' apart are ef f ective in resisting tangential

. hear. Tlie I membrane shell reinforcement in the region of multiple Codwelds

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.s as foll,eva: ,

1 l Merldlonal Reinforcing - 2 layers of $18 at 12 inches

- 4 layers of (18 at 12 inches l Hoop Reinforcing '

- 2 layers of #18 at 11 inches Seismic Heinforcing ,

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. , - y._ . _ , , _ . . _ . , _ _ _ _ _

. . . _ _ _ _ . - . _ -_,,.y- r., _-

l-In the region of concern let t n - number of bare with multiple Cadwelds

. N - number of other bars .

i I E - effective modulus of bare with multiple Cadwelds l

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i l E - modulus of other bars e

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.T3e change in.stif fness is: .

d (nEc + NE)

" f, x . _ 1 (n+N)E .

k M Tae increase in reinforcing stress is: ,

5 **r n +N _4 j.Ar n ec + N . .

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• For the oef f dional and hoop reinforcing the change in stiffness and stress are l

conservatively given as follows for the case of three closely spaced Cadwelds.

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'~ Cases withimore than three are uncommnn and do not affect the following results.

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i Meridional Reinforcement AK - -2. 7%

Af - +2. 8%

Hoop Reinforcement -

6K - -1%  : ' .

Af - +1%

.I 1he total l,angentini shear stif fiiens is a complex combination of aggregate inter-

.  ! Slight changes in the

! J ock, dowe5 action and diagonal reinforcement. s.tif f ness.

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ocal stiffness of the diagonal reinforcement vill not produce any measurable I

$hange in torni attIfness. -

I 1 he spprox mate increase in stress in the sci cic reinforcement in: . ..

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hismie Retnforcement- - aL l "

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e 3 1 .

CONCLUS10NSI . t .

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. c.rlangesinstiffness and stress have been conservatively computed and are ,-

s:: all. Thej stress inercove in meridione1, hoop and seismic reinforcing

.I cel is less than 1.5 Ksi. This utresa increase in due to a redistribu-st g

. U nn of int ernal forces induced by the localized sof tening in the vicinity

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' uj multiple, Cadweld spi lees. It is.not in any way related to increar.ed' i I

Ic ads or chlpnges in the cap.= city of the secLlon. The attength of the sec-

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'. tjon is not~

altered, only the "linearity'* of the global response is af fected. .

. 11 should b'e noted that thr operating thernal gradients produce an internal I '

distribut';1on of stress which in much more significant than the case of ra .

l m ultiple Cadwelds'and the effects of these gradients are recognized as in- .

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c onsequent$1. These cases are similar in that the stiffness and stress dis- i.

j Hence, the presence

ribution are af fected with no reduction in c'apacity.

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. t o:. multipidI Cadvelds as indicated by the field survey is of no significance ~.

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a. .: >-n ' MEMORANDUM

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File.__ _Mrc 452/81 i W.O.# 0016 h,,, ject EFFECT OF MULTIP1E CADWELDS ON_CBACILCONTROL

Reference:

A. SBU-43558 Question 3 Discussion:

Having reviewed the evaluation of the significance of Multiple Cadwelds in a given area on Crack Control, we concur with the response presented by UE & C.

R.

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/ AucKer Mechanical Engineering Group RKT/gbc cc: J. R. Hoffman J. D. Haseltine W

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8 a w.ms . e, BLUE SHEET .- as * - B 4.2.7 FORM - 001 PAGE 1 OF 2 MAR 0 2 1981 SEABROOK STATION 9 "O'

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rui uu' I c.@EQUEST FOR FOLLOW-UP ACTION

'^ NRC INSPECTIONS TO: J. F. Vought DATE: 3/2/81 Inspection item

Description:

Cadweld Splices - Series UNIT: 1&2 This is being issued to follow-up on a verbal commit' ment made by Mr. J. A. Grusetskie, UE&C Liaison Engineering, following a discussion with Mr. Verala, NRC. The subject matter was NRC unresolved item 443/80-12-01 and what had been done to resolve it. The corrective action to date was sufficient as far as it went but there was one question that still had not been answered. The question is as underlined on the attached sheet.

Mr. J. A. Grusetskie agreed to have Perini submit a list with locations, of all cadwelds that have been installed that violate ECA Ol/2127D and then UE6C will evaluate these.

Corrective Action Required: Perini has agreed to submit the list (s) to UE6C by 3/10/81 and then UE&C is to evaluate the information submitted. This evaluation shall be part of the response to this Blue Sheet.

_88 - _

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T Q',c 92 f 4 M i l' a 4 AA-Y l

Date Required: 3/12/81 Approved By: J. W. Singleton M

Requested By: bk, (

YAEC FOAE NOTE: Contractor is requested to respond by memo referring ident. number of this report.

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sesi. ores crv.vai costnAcran SHEET OF

- PROJECT CHANGE

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SE ABROOK STATION arv numers DATE April 1. 1981 8/21/81  ;

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cf W gt,AL ois ER 0 .1 2,1 2 7 D op. c c a. rc a. sac gi ;,g ,,g, ,,p,g,g,,,

DESCRIPTION OF CHANGE / REQUEST y ASME YES X _NOf SAFETY RELATED YES X NO U MA O NNSA 5STIA'CCER IC ALD WEE I D i SIP!Li lIC'E!S' : I! ! I- -

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, to rilar as .r e i r s l r e I r r ra irs I sc( a s i s e l s s pa p41 se l s r pe pe leo le s l*a le s I44 H s be H r I*a H o l sol s e l se l s s i p l ss l ee l s r l se l se leo l e s [ea ns l u i es ten z'-

Consecutive' cadweld' reinforcing' splices in all sizes and positions and in a U g

[" shall be staggered unless otherwise shown 'en drawings or other approved wi -'do

- d, , stagger length shalljbe. 26". .g. / j.

g ., Specific engineering approval is required f or stagger lengths less than 2 AUG 2 81 ,

~

" Number of cadweld splices in any single bar is limited to two (2) within a full b

+- ,' development length.'Any additional cadweld splices will be a minimum of a full DOC Pb M. length f rom any adjacent cadweld splices." . CONTROD -

.... RE ASON FOR CHANGE "cloloiDI '.EIElG'IiN:E'Ei REQUEST FOR INFO M i I R IiN I P! R G'I A' C T' Y C E i i; t i I#$

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. <. r e,

, q = c r a n s c r oocu=r.= r m ei ntersir.in in ierin in as "

e . ta h h elW ud whW ' guidelines

' bjects. This will provide'6!

1. ECA012127 Cl baire interim been established control, andon these to respond same Ins ection Number' 013.1 - - "

g

• r. . .t. ' n t.4 4 g i.y- f, r NRC . .# '

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i. # g .. , ,. i. . .. . ' l 'Rev. ~B adds draf t copy of ACI,1981 which changes sta er recuirements

b-l from 36" to 24"

1. F C R f/ggg4 Reve t: Further clarifies s agger reme

1. R F' I l N E V-comin'a zo ,Rev. D to clarify last paragraph P. J. Schlicte , Superv.

esAse t INITIAT ED ST TITLE OReamer T10N APP Ovt0 < -

WORKING DOCUMENT REOb BY: "* "'' " &

April 13, 1981 sac /ren DiscussE0irITM OATE FOR OmgetN ATOR FOR GR AF T S uP T. FOR REs. CONSTA Enem l AFFECTED DOCUMENTS Pip =e owes ontv auwera numer n =umera

{ t=Trn scismic occuer=T sF ae tic

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sue . s rc T eon as si ir n relasitolavireln so to ai n n relssleelrrirein so to re er 23 reirsIrelarfre;n sol si ro ri er as relas t rela rlee ln bolsi bth i '

D W G D W G l.i' ,

S P E C l1!4i ii S A R D '1 0 D W G  ! i i;l S P E C i 1l 4 i -1 2l i E R i l ! i i D W G D W G !IiI l $ P E C l 114! .13i l + S P [E !C ! ll!4 -i4-0 3 G D W G  ! : it . 5 D 0 l + S !P 'E IC . W S - 4 C -

1 DCN/ECA APPROVAL.S-PREPARED BY AA Haldar I8C N MECH. SERV N/A AD# WTEF- Tu g g g, [' .~ ~)(/A LEAD P ' "' LE . /A NUCLEAR N/A OtSC RE KM Kalawadih DISC SDEl AJ Hu izerDISCIPLINE' .

FSAR AFFECTED YES NO h . AwAITIN G J STA. G. N/A AS BUILT BOSTON- N/A STRUCT. KMK Y21S1 h _L DE

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APPROVE D///////ffM 3 , q S AFET3 REL ATED APPROVAL Mu on.wison' 't meli /acs consta eneR. r!E.L. D /

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A P P YES X NO 08 aty 8'1 YES OWNER # O' to aner B E DATE es(n ar ps nno TT REvtEw YOAfMA/ AA}O Af ,t/D u atou.ato if2lb"

/ rari f

.t.nd to the anticipat ; envir n::ntal condittons ,' EWolf2$f7h*

, - * .. s .

(1cmperature, humidity,etc.). All test samples siut11 s.

Jg (

cet the require::ent of Section 12.15,3,4, ,

(( gcg (b) - Cyclic Tests - Three specimens of the bAr-to-bac, , [

connection for each reinforcing bar size e.nd grade (to be used in construction) shall be subjected to  :

100 cycles of tensile stress variations frcal 5% to ,

90% of thI specificd minicium yield strength of the ,

retnforcing bar.' The specimens shall withstand the'

. [. .

cyclic test without Icss of static tensile' strength ,

capacity trhen compared +1th ifke specinen' in (a) and tested statically to failure fo11owing c7el'ic teses. .

12.15.33 - Welded solices and mechanical connections not meeting requir.: nents of Section C6 l h 12.15.3.3 or 12.15.3.4 may be used in accordance . 7 with Section 12.16.4 i

M/

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u.15.3.5- All welded splices and mechanical connections shall be visually examined by a qualified and. experienced inspector e to assure that they are properly installed at,the place ,

M i of construction. Where it is deemed necessary, the Engineer may require the destructive tests of product. ion -h splices to assure the compliance with Sections 12.15.3.3 and 12.15.3.4 12.13.3.7- Mechanical c=nnections abati be' staggered at'least 24 in with connections of adjacent bars if the unit strain over the full length of splice at 0.9 fy of the bar exceeds 0.,003 in per in and if the maximum ecaputed design load stress at the connection equals or exceeds 0.5 fy.

Coraant.12.15.3.7-nis differs from 349-76 12.16 5 S plicas of deformed bars and .

assentially only by a reduction deformed wire in tension in stagger (to be consistent) from 36 in"to 2f. in.

, 12.,16.1-Minimum length of lap for, tension lap .

splicos shall be as required for Class A. B or C spilee,but not less than 12 in.. where: ,

• Class A s plic e. . . . . . . . . . . . . . . . . . . . . . . . 1.0t, Class B splice. . . . . . . . . . . . . . . . . . .'. . . . . 1.3f, ,

Cla s s C s pil e n. . . . . . . . . . . . . . . . . . . . . . . . 1.7t, where I, is the lensile development length for the f- specifie** yield strengtn I, in accordance with

~

• .- 3LUE SMEET .

ius ' - B 4.2.7 FORM - 001

' NE OF

- SEABROOK STATION 013 NO' REQUEST FOR FOLLOW-UP ACTIO_N -

Sheet 3 of 6 - .

NRC ITISPECTIONS ECA 01/2127 D TO: J. T. Vought .

DATE: 12/19/80 Inspection item

Description:

". . UNIT: #1 .. . . . .

~

UE&C issued Soced Letter #246 on 11/24/80 which authorized Perini to cut approxi: ately 1000 rebar. These rebar were all cut at the same elevation and there is not enough

- 1ength exoosed to =ake a lap sulice so the rebar vill have to be expanded by cadwelding.

ACI-349 pars. 7.5.5 states that cadwelded solices shall be staggered unless certain conditions are met. In addition to this the NRC inspector has stated concerns on control of location of cadweld sulices in erevious discussions with YAIC and UE&C. re:

.. UELC Liaicon Intineering Infor=ation' Item #2 on SBU-40766. UI&C A*-15 allovs the use of a SAC to add recuired solices and ECA 01/06191 which revised s.

AP-15.

allows that on1v a verbal aooroval is reouired for additional sulices.

- Corrective Action' Required: Address the following questions and any other concerns that become apparent as a result .of your follow-up. 1. Is it the intent of FCCP-15 and AP-15 to allow changes of the magnitude of S/L d246 to be made totally with construction only sigs-

.off. 2. In light of ACI-349, what is the engineering i= pact of having alleved constructir

' to cut off all the bars at ,the same ' elevation with no consideration given to staggering.

C.- In light of question 2 and previous discussions with NRC on the i=portance of the

.. ... location of cadve34 splices in relation to other cadweld splices, i.e., SEU-40766, should

. the practice of allowing construction to add cadveld splices arbitrarily without engineerir.

input. .

• RES7 mSE: UE&C 7uwur Engineerint is studvina this problem. Ua do not have a final response at this time. This raises son.c significant design issues which if we uncer-stand then correctiv vere not considered as (CONTINUED ON PN:E 'DIO)

Date Required: 12/29/30 Approved By: J. W. Singleton

. YAECf_"-*' -

i

- - - Requesied By: b,(,

. . YAEC foAE .

NOTF Ctmtr.v. tor is rt:cuested to resnond bv rnemo referrino idnnt. number of this reoort

, - - - - - - - - - - - - - . - .- c, ,--, ,,y. ,-m-- --,-,,---m.-m---w - , - . - - - - - - - , -- -- .g ,,-,,- -.

BLUE SHEET Jan. 16, 1981 No. 013 Shact'4 cf 6 ECA 01/2127 D part of the original design criteria for the Seabrook plant. For exa=ple, ACI349 is not a design criteria listed in the PSAR or FSAR for the Seabrook plant. We are discussing the issue of cadweld locations with r.any people including senbers of the ACI349 Cer -ittee. Earry Scott, Assistant Manager QA Departr.ent. Leon Nasciranto, Chief Structural Engineer and Allan Hulshizer, Supervising Structural Engineer, are investigating this problem along with their staf fs. As can be seen from the attached telephone =amo, a r. ember of t,he NRC staff which was centacted by UE&C is not aware of any limitations with respect to the nu=ber of cadwelds per=issible with the given length of reinforcing bar.

We vill provide a final respense to this question on or before January 16 19S1. .

UI&C POWER INGINEERING FINAL RESPONSE:

This final respense is provided as promised on January 16, 1981.

The answer nu=bers correspond to those questions listed in the referenced docu=ent.

1. Tes, .it is the intent of FGCP-15 and AP-15 to allow changes of the magnitude of Speed letter No. 246. -

2. UE&C has evaluated the engineering impact of having allowed construction to cut-off all the bars at the same elevation, 2 feet above the contain-ment operating slab and the following conclusions are r.ade:

a) The impact of omitting stagger-in the Cadweld splice in the vallr; on the structural behavior and design basis forces is negliable.

b) There is no reduction in structural capacity.

c) These structural units vill perform as designed.

d) ne QA procedures insure high-quality Cadweld splice capable of

. developing the specified minimum strengths.

. . 3. In view of our evaluation, UE&C believes that the structural integrity of the valls are always raintained. Therefore, we intend to continue the practice of allowing construction to add cadweld splices as

• governed by construction requirements. However, in light of NRC concerns, we intend to set some guidelines on bars to be cut by construc-tion. Until these guidelines are set, construction vill be requested to stagger the caduelds by 24" wherever possible and consult engineering when staggeis cannot be achieved. In addition, construction s-ill be requested to reduce the number of cadwelds in a single bar. ECA 01/2127A vill be issued for this ' interim action by UE&C.

'l  ! .A u m

' Martin P. HanYon s" \

M?H:eao cc: H Shah MP Hanson JA Crusetskie DH Rhoads - --

AJ Hulshizer EB Scott HH Kat: I.S Nascimento

, , , .4 , g, ,. g --a- = - - = - -

- ~ - - - -

• e e p e a reco #

• call- io . A. J. Hulshi::: .. Of '

3peceber 17. 1980 t'

.( .e Mr. Asher (Wshintron. DC) TWE _ 2:25 a.m. ~

(1-301-443-5997) .

SUSJECT Prooosed Revief en to Ree. Cuf de .81.10 JOB NO. 9763.006 a

ORDER NO. Page 5 of 6

. . .. . ECA 01/2127 D

!  ;*Mr. Asher was centacted by Hecard h t: regarding the status of the -

i j

pr_opo, sed ,r,ev,isiens _to the- reg. , guide #1.10. Mr. h tz found that the

. reEt,s_f.on,_to res. guide is bh.h g finalized _ab.d__shp_ul,d_b,,e availab.le, f or public hearind*hin .a month or two, but *found that Mr. Asher vould be villing to discuss further broad topie_s with UE&C's engineering personnel.

~

.. Mr. Asher was een; acted by A. J. Eulshiser_,,to deterqin_e if the progos,ed

. revi,s_iens_to the reg.,,g_uide included any_li_= itations_vich respec,t _to_t,he .

e

' Su=i>e=:of._ cadweldi ?e.rs.i_s.sa_b_le_ .

. w.i.t..hit.h_e_E ve.n len8t.h. o_f___r_e_i_n_f_orcin8 ba _

Mr. Asher indicated..that_t;o_su,ch__lini,t,_hasl,be,en,__ included _in__ t.he, proposed .. , i l 1 .

s revision to the reg 2_gui,de and it has been the_p.o,si. tion, so far of..t.he ERC that the nu=ber of cadwelds has been governed by_eco'nc=ic f actors. .

i ._ . .

M; . As.her_q.ues,tioned_the peason_for. our,_thi:. king _,that _the_ug guid'e haid_ ,,

been revise'd to inclede the stated restrictions.

[ . ,

t . .

A._,J Rulshizer_. indicated _that_the,_NRC_residest_imspector (region 1) repor,tedly_ questioned __the .nu=ber_of_,,caducids util.1 zed withip_,giy.en, __ _

lengt_hs, of bar_s. their rupers have its origin in ths revision to reg.

nudde #1.10.

Mr. Asher reolied that. this_que,s_ tion has never come_,up_before and

,,,_ that ,the ,NitC site , inspector sliculd, feel f ree, to es11 them ,regarding ,_ _ _. _ _ ,,

their understanding ,of_the_qstter. __ _

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IT nem..ber 17. Icno Mr. Ather (t.', H r -ee . nt-i

- - - - - -- TIME 2:25 v.m.

(1-301-443-5997)

• SUBJE CT - Pionesed Revi ed e- ee o . .' _ r,, w #1.10 - . JOB NO. 9763.006 .

ORDER NO. Pace 6of 6 ECA 01/2127 D .

. .- 'ce: CF Cole .

DH Rhoads g- M . _ ._ ' /.J .

_ ..- . . . . DE 1!cCarri:;an .-

. .- . ~'

• E. Scott . .

..- H . 1*a f-. . .

1.5 nascimento

' ~~ .

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--- - - - - - - .71' Crusetskie .

7 - *

• M.#Ianson

• Y.

37 yought . -

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• JR D=ytryk - - --

~

~

.. . .. .- - . -- - File: 3.0.6; 3.0.1 . . .

~._- .

. . .. _. . _ . . . . c.

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.u

r v M MEMORANDUM hu11ted engineers.-~

i

,, vn No. 9763.013 OrricE: Seabrook Station LE-173 Power Engineering DATE: April 3, 1981 DEPT.

To: A. J. Hulshizer Cops Es : KM Kalawadia w/a::.

MP Hanson w/o att.

DH Rhoads w/o att.

JJ Ucciferro w/o att.

FRoM: J. A. Grusetskie GF Cole w/o att.

LE File w/o att.

MA Edgar w/o att.

SUBJ ECT: Public Service Company of New Hampshire RG Blair w/o att.

Seabrook Station hTC " Blue Sheet" No. 18 Chdweld Maps Showing Location of Multiple Cadwelds

Reference:

(1) LE-168, 03/17/81 (2) LE-169, 03/20/81 (3) LE-170, 03/24/81 (4) Perini Transmittal UES-81-219T, 04/02/81 No Response Required Attached is the fourth set of prints showing multiple cadweld locations in the Unit fl Primary Shield Wall. The remaining maps for areas primarily~in the containment internal concrete will be transmitted as soon as they are completed.

A We have extended our commitment date for an answer to 04/10/81.

If we do not have the remaining cadweld maps in sufficient time for you to receive them and properly review them we will again extend our commitment time for an additional two weeks.

~

i l

l ~

)

! J. A. Grusetskie 1

l

! JAG:knu Attachments l

bl'5 e

e b

. 1 HARMON & WEISS 200s S STREET, N.W.

SUITE 430 WASHINGTON, D.C. soooo-ties G AIL McOREEVY HARMON ELLYN R. WEISS TELEPHONE DIANE CURRAN (702)328 3500 DEAN R. TOUSLEY ANDREA C. FERSTER October 21, 1986 HAND DELIVERED FREEDOM OF INFORMATION Dennie H. Grimsley, Director ACT REQUEST Division of Rules and Records ~[b"7((O Office of Administration U.S. Nuclear Regulatory Commission 7735 Old Georgetown Road

!~W Bethesda, Ma ryland

Dear Mr. Grimsley:

4 Pursuant to the Freedom of Information Act, 5 U.S.C. S 552, g seq., the New England Coalition on Nuclear Pollution ("NECNP")

requests that you make available all documents that relate to the cadweld test and/or construction problem referred to in paragraph 8 of a letter from Stephen M. Long, NRC, to Robert J. Harrison, Public Service Company of New Hampshire, dated October 8,1986.

A copy of that letter is attached. Please note that this request may overlap paragraph 4 of another FOIA request made by NECNP on September 12,1986 (FOIA 8 6-678) .

NECNP is an intervenor in the Seabrook operating license proceeding. The organization intends to use this information in the licensing hearings to further the public's interest in the safety of operation of the Seabrook plant. Therefore we request that you waive any copying and search fees pursuant to 10 C.F.R. 9.14(c).

I look forward to receiving your response within ten working days, as required by the Freedom of Information Act.

, Si ncerely ,

Diane Curran Msy -

o ,

. RECEIVED DCT 1 7 1986

1. .. .. n,o, UNITED STATES

!T ..,, h NUCLEAR REGULATORY COMMISSION ,'

t l WASHINGTON, O C. 20555 s, ~~. i p

s Oct sB6 Docket tos.: 50-443

• and 50-444 i

Fr. Robert J. Harrison President & Chief Executive Officer - 1\ i Public Service Company of hew Hampshire Post Office Box 330 <

Manchester, hew Hampshire 03105

Subject:

Request for Additional Information for Seabrook Station, Units 1 and l 2, Errergency Planning Sensitivity Study i

The enclosed Request for Additional Information dccuments the oral and handwritten questions transmitted to Public Service Company of New Hampshire personnel and contractors during our meeting in Bethesda, Maryland on September 23, 1986.

Please provide your responses promptly to facilitate our review.

Questions or additional infoimation regarding this matter should be directed to the Technical Project Manager for the review of the Seabrook Emergency Planning Sensitivity Study, S. M. Long (301) 492-8413.

Sincerely.

-D5 _

I Steven M. Long, Project Manager PWR Project Directorate No. 5 Division of PWR Licensing-A

Enclosure:

As stated cc: See next page

, ,h rh A il f -

u 4'tl V pp .

?

r Enclosure l

REQUEST FOR ADDITIONAL INFORMATION SEABROOK STATION, UNITS 1 AND 2 DOCKET N05.: 50-443 AND 50-444 EMERGENCY PLANNING SENSITIVITY STUDY

1. Describe how the overpressurization calculations made by SMA were checked or design reviewed.

2. A meeting should be arranged with the originator of these calculations to assist the BNL reviewers in following these calculations and understanding the assumptions.

3. Occument the basis for the assumptions in the calculations. In particular, explain the uncertainty factors assigned to various pressure capacities.

4 Explain the mechanism for transferring the load from the penetration sleeves to the containment wall, in particular, the equipment hatch, when subjected to high strain conditions. Explain how the rebars around the penetrations were assessed to assure that they can resist these loads in addition to the primary pressure induced loads.

5. The calculations use a rebar ultimate stain value of 4.7%, i.e., more than 21 feet of linear extension for the hoop bars. This linear extension under the high pressure load will be accommodated by formation of cracks in the concrete totaling approximately 21 feet in width, Justify the assumption that the pressure loads will be carried proportionately by the linear plate l and the rebars (similar to the elastic condition) in this highly cracked condition. Also address the potential for developing a crack large enough for the local extension of the liner plate to lead to its failure at that point.

6. Was compatibility of strains in the rebars and the liner plate satisfied in the calculations? For example, the outermost hoop bars will fail before the inside bars and the liner plate reach their respective ultimate strengths.

Was this fact reflected in the calculations? In addition, how is the biaxial stress-strain state of the liner plate considered.

7. The combined tension, shear and bending effect at base and spring line I levels was not considered in the calculations (Ref. p. 35, assumption 6).

Verify that the combined effect does not change the conclusions of the analysis.

ee *

• • • • *15"SP-***#

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. Since 31 cadwelds out of a total of 169 test samples failed at a stres lower than the rebar ultimate strength and there was apparently a construction problem concerning staggering of these welds, provide (N. justification .._________....--

for not using a_ reduced-ultimate strength for the rWE-- '

9. The containment analysis is based on an axisymmetric geometry and loading.

' This is not the case due to the presence of adjoining structures such as the fuel building and main steam and feedwater pipe chase. Identify these axisymetric conditions and assess their impact on the failure modes and analysis.

10. Only a sample of pipe penetrations are considered in some detail (X-23, X-26 and X-71). The justification to consider only these should be provided.

11. A structural evaluation of electrical penetrations should be provided.

12. The basis for the leakage area assigned to the flued head at failure should be provided.

I

13. A more detailed evaluation of the impact of punching shear at the Fuel Transfer Eu11 ding should be provided.

14 Clarify the extent to which double ended piping failures have been considered in the overall containment performance assessment. Provide isometric drawings of all piping attached to containment penetrations.

15. In PLG-0465, page 2-10, Figure 2-3, the conditional frequency of exceeding whole body dose vs distance appears to be driven by the S2 scurce tenn. If this is the case, please describe all accident sequences (internal and external events) that contribute to the frequency of the 52 source term given in Table 4-2, pg. 4-7. in particular, define how

the timing and size of containment leakage was determined for each of I these classes of accident sequences. Justify the appropriateness of the

! binning of each of the accidents into this particular source term.

I

16. Provide justification for the liner yield stress increase from the specified yield stress of 32 ksi to a mean yield stress of 45.4 ksi.

17. Indicate the correlation between containment failure sequences and the containment failure modes.

18. Provide the basis for concluding that the sight glasses in the hatches will not fail under high containment temperature and pressure conditions.

19. Document the effect that the recent update in seismic fragilities will teve on the conclusions of the PSA results.

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s 3

20. Assess the impact on risk of using the assumption of ultimate containment capability predicted by VE&C analysis (150 psig).

21. What is the impact on risk from accidents during shutdown and refueling when the containment function may not be available?

22. It is the staffs understanding that preexisting violations of containment integrity were " included" in the PSA by assuming the average effect was to raise the containment leak rate to the design basis value of 0.11/ day,

a. Compare this assurrption with the contairment integrity violation data presented in huREG/CR 4220.

1

b. What contributions would these containment integrity violation data 4

make to the probabilities for each of the release categories (Assume the SSW category is redistributed over all the appropriate categories by the conditional probabilities of preexisting leakage paths of the size appropriate to each category).

23. a. Provide a narrative description that quantitatively delineates the dominant contributors to the dose probacility vs distance curves and the early fatality probability curves. The dominant release categcries should be specified and the dominant accident sequences i contributino to each of these release categories should be specified.

l The probability of occurrence of each release category should be I

stated. These data should be provided for the current study and for the original PSA results. Changes between the two studies I

should be attributed to specific differences in the analysis.

b. Provice a set of early fatality conditional probability curves for each release category, assuming evacuation distances of 1 mile and 2 miles.

c. Provide the conditional mean risk of early fatality for each of the curves provided in b.

24. Provide a quantitative description of the effects of the following differences between the original PSA and the current study:

a. reduction in probability of core-melt Y sequences ~

b. factor of 1000 scrubbing of releases through RHR seals

c. change of release category (S6 to SI) for unscrubbed event V sequences.

The effects should be described in terms of differences in risk curves for early fatalities and fur 200 rem vs distance. .

25. Provide a list of all paths for loss of RCS inventory outside containment.

Show how these have been considered with respect to LOCA and with respect to containment bypass for radioactive materials following core damage.

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--- m - , - - , * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

's 6

O

26. Indicate the extent to which the effect of local deflagration / detonation of hydrogen qas concentration in localized areas both inside and outside the containment has been considered in the assessment of risk. Include a discussion of how weak areas of containment have been considered in your assessment, for example, the containment is considerably-weaker in its resistance to pressure loading from outside the containment.

27. Discuss the effect on risk of hydrogen deflagation/ detonation in the RHR vault.

28. Identify any penetrations connected directly into the containment atmosphere which rely on any remote manual or manual valves for isolation.

~

' ' ' ^ ~ - - - - - ...,,_,,.mn,.,,__,n._-,, , __ _ ___ _ _ __ _