ML20094P252

Discusses Util 820428 Telcon Notifyng That,While Drilling Well in Q Area,Electric Duct Bank Struck.Drawings Indicated Duct Bank Elsewhere.Investigation Continuing

ML20094P252
Person / Time
Site:	Midland
Issue date:	04/28/1982
From:	Shafer W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:	Landsman R, Gerald Williams NRC
Shared Package
ML19258A087	List: IR 05000329/1978020 IR 05000329/1981012 IR 05000329/1982007 IR 05000329/1982009 IR 05000329/1982014 ML19258A086 ML19351C947 ML20093B251 ML20093B495 ML20093B616 ML20093B708 ML20093B747 ML20093B900 ML20093B940 ML20093C001 ML20093C006 ML20093C017 ML20093C025 ML20093C030 ML20093C035 ML20093C068 ML20093C073 ML20093C079 ML20093C082 ML20093C101 ML20093C104 ML20093C108 ML20093C116 ML20093C174 ML20093C189 ML20093C196 ML20093C226 ML20093C231 ML20093C262 ML20093C318 ML20093C324 ML20093C347 ML20093C354 ML20093C374 ML20093C377 ML20093C390 ML20093C394 ML20093C398 ML20093C405 ML20093C440 ML20093C444 ML20093C649 ML20093M884 ML20093M994 ML20093N005 ... further results
References
CON-BX19-001A, CON-BX19-1A, FOIA-84-96 NUDOCS 8408170090
Download: ML20094P252 (1)

Text

._, ~.

h" U h

' UNITED STATES

'/

o, NUCLEAR REGULATORY COMMISSION E %.. -

h

.p* %'d ;#{E{ e atatou set

'" / c 7se moosevati meAo

,8, oles ELLvw. itusois sois7 April 28, 1982 MEMORANDUM FOR:

C. C. Williams /R. B. Landsman ROM

• W. D. Shafer

SUBJECT:

MIDLAND At 3:15 p.m. on April 28, 1982, Mr. Walt Bird called and notified me that while drilling a dewatering well in a Q area they struck an

{

l electric duct e. bank. He stated they should not have hit the duct j

i because they were probing for such obstacles and their drawings indi-cated that the duct bank was elsewhere.

Investigation continuing.

a er p.

I I

I SW i

q hlum Y

1 en

=

,e 8408170090 840718 PDR FOIA RICE 84-96 PDR

L J-

~

l

- :s LBPj82-35 y,.

d' i

.. i i

UNITED STATES'UF AMERICA l

I NUCLEAR REGULATORY. COMMISSION 1

-i

~

. ATOMIC SAFETY AND' LICENSING BOARD Before Administ~rative Judges:

l l

Charles Bechhoefer!.. Chairman i

Or. Freder.ick iPL Cowan i

j

'R4,lphi S. Decken i

A

)

. Docket Nos: 50-329 OM In the Matter of

)

50-330 OM

~~

l CONSUMERS POWER COMPANY Docket Nos. 50-329 OL j

50-330 OL 4

(Midland: Plant ~, Units 1 and-2) )

i

)

April 30, 1982 3

MEMORANDUM ANOTORDER (Imposing Certain Inter.im Conditions Pending issuance of Partial'Initiai Decision) l l

., Pending before this Licens.ing Board :areiconsolidated proceedings i

arising out of the NRC Staff's December.6,1979 Order Modifying Construction Permits No. CPPR-81 and No. CPPR-82-(OM proceeding), and the applil cation by a

t Consumers Power Co. for operating licenses. for Midland Nuclear Poder Plant.

..w.

Units 1 and 2 (OL proceeding). / The facility, currently under construction, consists of two pressurized. water reactors located in Midland,

(-

Michigan.

i The Modif:ication Order was generated as a result of the excessive l-settlement which occurred with respect to the facility's diesel generator

~

i 1/ The proceedings were consolidated at the. request of Consumers ' Power Co.,

~

the Applicant in the OL proceeding and the Licensee in the OM proceeding (hereinafter referred to as " Consumers").

See Prehearing Conference Droer, dated October 24,1980 (*unpubl(shed) 9 i

i q;,, n r-r, j

w.) U.) U D 6 J---

l i

b o

f.

e j

a

-~ ~ ;

___T__..,

="

~~

~~

~

' ^ ~

~

'~

l n.

1' 5

i i

l '.

i building and other pjant structures.. Hearings;whichhavebeenheld[todate i

concern the soils settlement issues raised: by the: Modification Order, is

~

well as related contentions of intervenors.:in each of the proceedinsis.- (The majority of the soils settlement contentions. have been sponsored by Ms.

Barbara Stamiris, an intervenor in the.QM proceeding.) As reflected in our i

Memorandumbf October 2,1981, we have determined to issue L

7 separate partial ~' initial decisions dealing with various aspects of the soils j

issues.

The first, now under preparatioin deals with quality j

assurance / quality control (QA/QC) and! management attitude issues, as

, delineated in the October 2,1981 Memorandum.. With limited exceptio'ns, the i

5 record on these matters was c.losed on February 19, 1982, foll'owing s;ome thirty-five days of hearings.3_/ The second will deal with proposed, i

remedial actions to correct the soils. settlement problems.

Hearings on t

thess matters are not yet completed,' part.ially as a result of the as-yet

{

a developing positions of all parties on ttiese questions.

I i

With respect to the QA/QC and management: attitude issues, proposed findings of fact: and conclusions of l'aw,: and supplemental proposed findings I

and conclusions covering matters as to which' the record was reopened, have i

been received from all interested partieh and ! Consumers has just recently filed its replies to each of the proposed and. supplemental proposed I

l findings and conclusions of the other parties. During the course of our 4

i

[

2/

Hemorandum (Concerning Telephone Conference Call of September 25, i

1981 and Appitcant's Motion for Partial Decision), dated October. 2,1981

(

(unpublished).

t 3/

Certain aspects of these issues will: remain open until our second 7

partial initial decision.

N 3

i

~

n;.

~.. ~. c.:.

. -. =

r.,

I t

-3.

\\

m t

review of these various. filings, as well as of the entire. record, we have r

+

a

\\

determined tirat certain condi.tions governing further construction, as set forth in Section VI of this Memorandum and Order, should be put inth effect I

imediately, pending the completion of our'rev.iew and the issuance yithin l

1 approxiinately two or three months of our first Partial Initial l

Decision.'4/ Our reasons follow.

i

. a.-

I.

Backenound I

Under construction permits such as are:in effect, for the Midland plants, j

i.

a permittee may normally engag.e in construction activities in accordance s

l with the principal architectural and engi.neering criteria and environmental commitments set forth in the applicatdon for the facility and the i

construction-permit hearing record, without seeking prior approval 6f the NRC Staff.

The permittee undertekes such activities at its own risk; they are subject to Commissioni approval before;an operating license may be 4

i granted. See 10 C.F.R. j50.57; Cf. Northern Indiana Public Service Co.

1 (Bai11y Generating Station Nuclear-li), CLla79-11,10 NRC 733 (1979),

i reversed on other grour$ds, sub. nom. People of the State of Illinois v. NRC I

^

g 8

I i

4/

This procedure has been previously! utilized by the Appeal Board with

~

respect to these very same: reactors. ALAB-106,6AEC182(1973).

We note that, in a telephone conference tall on April 28, 1982, the Staff indicated that it might reconsider. certain eariter testimony i

expressing reasonable assurance that Consumers' QA program will;be appropriately implemented with respect.to future soils construction activities (Keppler, prepared testiony,.p. 9, fol. Tr.1864).

It i

requested that we cancel certain near-term. hearings which we had scheduled, and we did so.

Memorandum and. Order (Cancelling Evidentiary Hearings and Conference of Counsel or Representatives), dated April 28, 1980 (unpublished).

As a result, our first P'artial Initial Decision could be delayed beyond the time. frame.we are now projecting.

3 a

l L

H i

i

. - - ~

i.

~. w -..wn

~-

~

i :

s e

iM j

f S-(iii) removal and replacement of f~ill beneath the feedwater isolation valve pit area j

+

+

(iv)'

placing caissons at the ends, of the auxiliary build,ing i

I t

t electrical penetrat. ion, areas; (v) compaction and loading tacti.v.ities;

+

(c) construction work in soil materials'. under or around safety-related s,ts.uctures and systees suchr. as fieTd: installation of condhits and i

piping.

l Had the hearings in the OM proceeding not'been requested, Consumers 6

'could not have undertaken any of the foregoing a ti iti 1

es without submitting c v an a:nendment to its application and obtaining construction-permit '

l 4

amendments authorizing such activities.. Sinceithe hearing was requested, the normal construction permit authority remains in effect, and no i

i construction permit amendment (or other NRC ' authorization) needs to be i

sought in order for Consumers to engage in the activities in question.

~!

Both'the Modification Order (Part V) and.the Comission's Notice of' Hearingof(March 14,1980 (45: Fed. Reg.18214i March 20,1980) stated that this Board is to consider' and decide the folilowing issues:

{

(1) Whether the facts (concerding quality deficiencies) set forth in

}'

Part II of the Order are correct; ano l

(2).Whether that Order, should be sustained.

11.

Facts.Underly.its Modi.fication Order One of the cases for the Modification Order was the allegation ;that 1

i there had been a breakdown in quality: assurance related to soils.

Another *

(

s l.

l w--.

Tr *

• e ir'"*'

t-*'N-w

=V C

s"

"*'.'---'M-

w-='w*-PWm'--*-w-r--

-www--y

--g--eggwww-ww,,-wy gy-gg-pywgp

-wy

-+-m-w

-g.r

,wem-+g-----ww-91r y-- - ---

g::.

i :

)

l j

4 j

1

i (D.C. Cir. No. 80-1163, July 1,1981%

The December 6.1979 Modificlation Order would have modified this regine! by prohib'iting certain construction i

activ4 ties with respect to safety-related. structures and systems affected by i

l I

the soils settlement problems which have2 been aired in the ongoing i

consolidated proceeding. Viic proh'ibited. act.ivities could not be undertaken j

.s

+

absent (1) submission of an amendment:to thet application seeking app'roval of remedial act+ons, and (2) issuance of an amendment to the construction i

permits authorizing the remedial actions;.5,,,/.. The Modification Oroer

~

further provided'that a hearing could.be requested by Consumers or other s

interested person and, if it were, the Order would go into effect only as a result of an order made following the hear.ing 6/

I lhe construction activities which the Fiodi.fication Order would have prohibitedconsistofthefollowing:1/

(a) any placing, compacti.ng, or excavatingi soil materials under' or around safet.y related structures ano systems; (b) physical implementation of remedial' action for correction of l

I soil-related problems under andiaround. these structures and I

systems, including but; not lim.ited'.to::.

i (1) dewatering systems (ii) underpinning of service > water 6uilding l

i 5/ Modification Order, Part IV.

The Modif.icat. ion Order has been

~

admitted into evidence as Stamiris Exh.

3' Attachment 15 (Tr.

2479).

6] Modification Order, Part

.i 2/ Modification Order, Part IV. '

4 6

. sw t

)-

k r

i i

.1 4 l i

l '-

j f

basis was that Consumers had not provided the: information which the !,$taffl and its consultants required to permit.a thorough safety review of proposed remedial actions.8/. As a result of these deficiencies,' the Staff j

i i

concluded that it did 'not have reasonable assurance that the safety-related portions of the 51dland facilities would be so constructed that they could i

+

I i

be operated without undue riskito pub _lic health and safety.

-l.

With regard to the first basis, Consumers.and the Staff entereh into a stipulation on June 5, '1981, in whichiConsumers conceded that prior to s

1

?

December ~6,1979 there were quality assurance deficiencies related to soil i

t construction activities.

Consumers agreed:not.to contest the Staff'.,s conr.lusion: that these deficiencies constituted. a breakdown in quality

+

c i

assurance with respect to soils placement at Midland, and it acknowledged that the deficiencies constituted an adequate basis for issuance of the

'i I

Order.9./ With regard to the second basis. fore the Order, the Staff and ConsEners entered into two additional stipulations in which Consumers agreed not to contest that, as of December 6, '1979.. the NRC Staff had insufficient information to evaluate the proposed remedial

• actions for the auxiliary i

building, for the borated water storage tanks:and underground i.

10/~

)

piping l

i i

(-

8/ We are here making no findings andireaching no conclusions with

~

i respect to a third basis for the Order, an alleged material f alse statement.

Hearings on that subject. are not yet completed although we have heard testimony on the management-attitude aspects of the alleged

• tatement.

p 9/

Applicant / Staff Joint Exh.1., following Tr.1175, admitted at

~

Tr. 1188..

10/ Applicant / Staff Joint Exhs. 2 and 3., dated December 1, i981 and February 9, 1982, respectively (Tr.: 5447', 7164).

o L

p

-.----i------

,3

..,._,m

i j

7.

l; l

t r

As a result of 1.hese stipulations,.We are able at an. early stage of our

~

i review to conclude, with respect to the. first hearing issue, that the facts set forth in Part 11 of the Modification Order (to the extent they relate to soils. QA deficiencies and the. adequacy on December 6,1979 of the i

j i

Staff's inf rmation to review remedial' act. ions) are correct and constituted S

an adequate bas.is for issuance of the Order.

Consumers, the NRC Staff, and i

intervenor~ffarbara Stamiris each submitted; proposed findings to this ef f ect.1.1/'

i f

1 III.

Facts Giving Rise to Interim Requirements I

i We have not yet completed' our revtiew of the second hearing issue--i,.e.,

whether and, if so, to what extent, the.Modif,i' cation Order should be j

sustained.

Consumers has described this issues as "whether the safety issues

[giving rise to the facts set forth in Part. il of th'e Modification Order]

have been resolved so that the quality. assurance program with respeht to soils is now being properly implemented. and. there'is reasonable assurance i

i I

i such implementation will continue through.the construction t

process."NI Ms. Stamiris has described it somewhat similarly, as,

"whether,as a result of revisions, improved implementation, and other factors, this Board has reasonable assurance that the QA and QC programs t

will be appropriately implemented with'. respect to future soils construction and remedial activities".13/ However, they' reach dif ferent answers 'to this question.

i 11/ ' Consumers Proposed Findings 135;: Staff Pt oposed Findings, U 236-237; Stamiris Proposed Findings, 1,10.

H/ Constaners Proposed Findings,1,37 [ sic; should be 36].

• M/ Stamirts Proposed Findings,110.

i I

i t

^

~~

,e--

-,nw.---

-m--

-,y---,,,,y,-,--g

,-,m,n----

,,,,w-o, e--wm-w a_mg

-e,,,e y-m.,---,, -

--w--w..,.

---

w-r

~

l I

i 8-i-

i j

Consumers asserts that, as a result of organizational and proeddur,41 2

, changes which* it has put intor effect since the i;suance of the Modi ication Order, its QA program is now being properly implemented.

It urges ds to i

find reasonable assurance that the future. soils constru'ction activitfies i

including the re$mdial actions;tak~en as a; result of inadequate soils'

+

+

i placement will be accomplished.in accordance with.QA principles of p'ublic health and'sefety.14./ On the other hand, although Ms. Stamiris I

concedes that Consumers' organizational chartges-represent a positiv.e 5

l response",15/ she nonetheless: concludes that:the implementation of A at

' Midland is inadeouate16,/ and that the. san;e.' kind of problems and

.c weaknesses currently exist as had lead to problems in the past 17/

She would have us put the Modification Order into effect and shut down soils,-related construction immediately_18/

• The NRC Staff also gave !

its reasonable 'ssurance that the QA program would be properly l_

j a

t I

4, l

4 i

,14/ Consumers Proposed Findings, 11 81-83.-

15] Stamiris Proposed Findings, 1 222..

'e j6/ Stantris Proposed Findings, 1 221..

2 / Stamiris Proposed Findings, 1 225..

I 18/ Stamiris Proposed Findings. T 254;! Part III.C.

I i

,m..e.

• P""'*

e w

- y s.

,--..w-e-----

y-w ww-y%-.,-y.r.-9 g- - - --

,-.r,,-4,m--g-m.-#ym-*we-.

w.i-.ga-'

W.-ee-r

+-

--Nw

+--r-*veew--' - +f-$r'-vWC"

--~-- -

~

^

i l

g,,

j I

...e

)

implemented,E/. although at least one of its witnesses expressed some 4

reservations (Tr. 2441-42 (Sallagher)),. 20h 3

. We do not at this point in our reviewiexpress any opinion with' respect to those posit-ions--except to note that none :of them is baseless and all

{

have. evidentiary' support.

The. retolution of this broad issue will,;as we j

+

have:seen, affect the degree to which and tl6e manner in which soils-related construction activities (and particularly remedial actions) will be!

permitted to continue.2,1/

4 As background for our approach to this question', we deem it im ortant t

4 to note that the QA/QC deficie'ncies which, are: addressed by the Modification Order are not the first instances where Consumers has experienced difficulty in' properly implementing its QA/QC program..-

The Appeal Boaro pinpointed one such instance in ALAB-106 (fn. 4, supra).. and it imposed conditions designed to alleviate the deficiencies which it found te exist.

Later, questions were raised concerning the QA/QC organizationi being utilized for this

~

f acility.' ALAB,132, 6 AEC 431 (1973)r. ALAB-147, 6 AEC 636 (1973);

LAB-iS2, 6 AEC 816 4.1973).

Subsequently, the Staff. issued a show-cause order which 1

J.9/ NRC Staff Proposed Findings, f 375..

i i

20/ Mr. Gallagher stated that he suppor,ted Mr. Keppler's conclusions

~-

concerning implementation' of thet QA program " entirely" but added that he "would itke to see some other-things to be included" (Tr. 2455).

See also fn. 4, supr.,1 2.

21/

As we have pointed out (pp. 4 5, supra), the most stringent

~

condition we could impose on those activii. ties under the Modification Order would be to prohibit such activities pending submission of an amendment to the applications and issuance of construction-permit amendments authorizing remedial action.. All or any portion of that t

condition could be put into effect.

Cf (Marble Hill Nuclear Generating Statio_f,. Public _ Service Co. of Indiana n, Units 1 and 2), CL1-80-10 NRC 438 (1980); Wisconsin Electric Power Co. (Point Beach, Unit 1),, IT CLI-80,38,12 NRT 547 (1980).

i I

l

.,w*

• = = = * *

,.-e-

,g.-

,.-,-_aq y,-_

.y.

,y-_-,_-,-,.WMt'.t- ' -

C

• -'W P-t M--s=vw.--r--e e'ery9-we--e

-.eMem ywc9-w

-..v-=-e rrm w9' S q-'v-=e-

,,As..

...ms.

'~

l

.j

~

...1 10

(-

i i

was founded on other QA/QC deficiencies,, and additional corrective actions N

i were mandatedt ALAB-283, 2 NRC 11 (1975).. clarified. ALA8-315, 3 NR,C 101 i

(1976$ During that show-cause proceeding, the Appeal Board remarke'd that l

I i

l l

"non-compliance with the Commission's. quality assurance' regulations ;is * *

• i a problem which has plagued the cdnstruction; of this facility." AL 5-270,

+

i 1 NRC 473, 476. (1975)..2,2/

i t

i With th4.s: history before us, early in this proceeding we expressed l

t concern about the adequacy of and the. potential safe,ty impact of ongoing f

construction activities (Tr. 754-55)'.. On the opening day of the hearing, I

the Staff responded to our inquiry by presertting testimony regarding' i

j soils-related construction of the type that would be going,on during the j

period of time Lefore we could. issue a dects; ion governing Construction encompassed by tt e Modification OrderM/' From that testimony, it appeared to.us that Consumers was at that: time : consulting with and seeking i

1 approval nf the Staff before engagingiin any of the construction activities l

l there under consideration--1.&, installation. of 20 permanent back-up i

i interceptor wells in the area near the. Serv. ice Water Structure and the i

Circulating Water Intake Structure, and surchariging of the two valve pits 22/

See also Board Exhs.1 A and 1B (Tr.;1875).. which contain a summary of problems, experienced at Midland since.the start of 3

construction.

I 23/

Testimony and Supplemental Testimonyiof Darl S. Hood, both fo11' wing o

Tr.

1097.

i e

e e

i i

TX

- A~%

- ~ ~ ~ ~ ~

' ' ~ ~ ' ' ' ' ~ ~ ~

~

' ~ ~

~ ~ '

l-r 11 i

t i

which are ad.jacent to each of the Borated Water Storage Tanks 2{/.j Although all of the outstanding questions raised by the Staff concerning l

thosh proposed remedial activities had not. then been resolved, the Staff I

expressed its " reasonable assurance" that the. activities would be pe,rformed in am acceptable' manner.M/

We ihterpret that reasonable assurance, l

/.

+

j conclusion as premised upon Consumers' affording the Staff the opportunity t

.to review the proposed resolution of the unresolved questions 26/

In addition, Consumers advised us that; in Eebruary,1980, it h, ad voluntarily comitted not to proceed with.further remedial actions without

' Staff review and concurrence.E/ (Insof ar as the-record reflects, this t

i comitment appears to have been an ora] one; not reduced to writing l prior.to j

2 its incorporation into testimony in this proceeding.) That Consumers will I

provide the Staff with sufficient informatio[r to permit a thorough safety I

review is loherent in this commitment..

i' We find no indication in the record that Consumers has failed to ho.nor this comitment.

For its part, the Staff agreed that it would accept I

i information through meetings and presentat. ions. rather than an arr.endment to i

24/ He. d, prepared testimony, p. 2.

Those.were the only two soils-l

'~~

related activities then under wa Consumers in the near term (Tr. y or planned to be undertaken by 1.112)'..

.l 25/ Hood, aupplemental testimony, p. 3.

Subsequently, on December 10, 1982, the Staff approved the install.ations of S additional temporary dewatering wells.

Staff. Exh.13 (Tn. 690.1).

26/

Hood, prepared testimony, p. 3; supp test., pp. 2,3; Tr.1113-14,

~

1119.

g/ Testimony of Gilbert S. Keeley, fol. Tr.1163, p.13.

I

~ ~ ~ '

~

?

_,.1

~~

i j

~

~ ' !

12 -

i y i

I.

the application. Beyond the two matters. about which the Staff initi,all.y i

testified, the Staff has utilized this arrattgement to approve such !

I activities.as construction of access shafts and a. freezewall in preparation 6

for underpinning the auxiliary-building.and feedwater isolation valv~e i

pits,20/ angamy' drilling activit{es:near seismic Category 1 underground utilities and structures (Tr. 5485-86).

During the hearing, 4

Consumers agveed that the commitment would be extended to the matter. of crack evaluation, a question which Consumers, judged to be less impor. tant I

than does the Staff (Tr. 5735-38). As far as we are aware, certain j s

additional remedial actions to whichithe. comitment is being applied are i

currently under review or in progress:

t I

From the present stage of our review,.it appears that Consumers' j

i voluntary agreement has resulted in adequate-Staff surveillance of the proposed remedial' actions covered thereby6 prior to Consumers' comencement j

of the remedial actions. Consumers itself has. acknowledged the usefulness

~

to it of its consultation with the Staff prior to the initiation of emedial activities ((Tr. 5660-61). At this time,. we are making no changes tof the 1

' procedures utilized under this arrangement l

It is important to note, however; that Consumers' comitment doe, s not extend to all the activities which Part' IV off the Modification Order would l

i have prohibited (Tr. 1202-1212, 1390):

The. scope of the oral comitment is not clearly defined. While it appears essentially to cover those major 28/ Letter dated November 24, 1981, fro'm DarliHood.(NRC) to James W.

Cook (CPC) (Staff Exh. 5 Tr. 5467-)1

. l l

i i

L-

,._,..,,,,,.__.-e,,

,_,p.,,,,_,,,,,.,,,.%-

,._y

,,_..,__,,,,,,,,-,e eu--"*r----w-Nw

-ie.-1'-

e e-e--*

w P-

^^

.__ _. _. _ -c i

o

, i i

i i

i reInedici actions Within the scope of Section 1(b), but not activities l

1 falling withki Sections 1(a) a,nd 1(c); of Part IV of the December 1979 Orde'r fTr. 1450-1422), there is some. ambiguity. whether certain acti ities may fall within-Section 1(b) or one of the ether categories.

Although w'e have no objectibn to the. Staff / Consumers working h

+

relationship for those portions of the remedi:a.1 work to which the comitment

.. applies, several matters of record cause us to be dissatisfied with the limited scope of activities covered.

More. specif.ically, as a result of the matters described in this section of this Memorandisn and Order, auginented by

' the related information appearing in Pant' IV,. we are of the view 'ch t certain activities outside the scope of Consumers' comitment but within the coverage of the prohibition in the Modifi~ ation Order should be subheet to c

prior Staff review and approval.

I

.t i

The first of these matters which gives us concern.is that of i

f underground piping.

Consumers. proceeded with, work associated with 1

underground piping which carries cool.ing water essential to safety without seeking oc:, receiving formal Staff concunrence (Tr. 7784,7788a).

This~ work

+.

would clearly have been prohibited unden Part/ IV, Section 1(c) of the f

Modification Order, and it could also,be interpreted as falling within i

i Section ib (Tr. 7788c).

The record.is confusing as to whether the Staff' i

i regarded Consumers' commitment. as in f act covering that type of remedial.

action (Tr.

7781-7783, 7788a-7790, 7894-7901)t,9_/

The Staff expressed l

2 i

29/ We disagree with Consumers' response to Ms. Stamiris' Proposed Findings and Conclusions, T 8, pp. 6.-7.

l f

I

• • ,.._-.~,.,,.--,,,,,~~~cv.n-...~~.r~,~y

,,-,-,.,.,..wa-.y,-.,,n-

,,----,..m

--.- ---,,, -~.,....

,_n.

._g__

1.

l Tam.

f

!,F the opinion that underground piping should be covered by the coninttment, (Tr.

l t

7788c,7789,7899). Underground pip.ing was of concern to the Staff ' prior to i

its issuance of the Modification Order 30/* One reason we believe it essential that safety-related activities 1 sucht as the rebedding of piping l

l l

l should have prief full Staff revifw and. concurrence is that once such work

+

is performed and the piping then recovered with earth, it is no longer accessible.for inspection for such concerns as have been identified during the course of this hearing--e_.,g., corrosion,(Tr. 7683-86,7827-35),

deformation (Tr. 791214), quality of foundation soiis (Tr. 7911), pipe j-l

' welds- (Tr. 7652-56), and condition of p.ipe wrapping materials (Tr. [7860, i

7914-15). Therefore, adequate QA/QC surveillance is fundamental to, assuring safety. The Staff has expressed its desire, in f act, to review such matters i

i as compaction criteria and procedures prior to.the work taking place, and to j

N '.

be able to inspect the work while being performed (Tr. 7899).

Moreover, the Staff has stated that it had insufficient soil-profile information to l

.. evaluate distortion in pipes buried in soilsi which have settled.31/

The second reason for our requiringi further Staff review and approval prior to the start of soils-relateri construction differs from the first in l

that it does not stem from a single typetof construction activity.

Rather, it pervades the entire spectrum of soils-rela,ted construction activities.

As a resuit.of Board questioning, we have some doubt whether, in the absence 30/

!.E. Rept. 79-06, dated April 4',1979 (Stamiris Exh. 3, Att.

8, at

p. 5).

31/ Kane, prepared testimony, fol. Tr. 7752, p,. 3.

e i

i I

n

_ _ _:n

_ n _..

n :.

~

'o I

i i

15 9

i i

i of Staff review and approval, Consumers would ' carry out certain remedial soils activit.ies using appropniate QA procedures and principles.

It.s l

g wittjesses presenting the remedial plans.for the auxiliary building were unsure of the manner in which QA principles.would be applied to that i

operation (Tr. 5530-32).

With respec.t to the engineering of the remedial

, +

l actions, Consumers was able to describe the QA procedures it had already i

.followed (Tr 5718-20), but it also. indicated that it did not consider the j

e engineering a problem ar'ea and was therefore not applying any specialized l

procedures to those activities (Tr. 5622).--despite the f act that it had to I

v formulate and rework its planss four dif.ferent times before it obtained a l

s system acceptable tn the Staff (Tr. 5647-58).. Consumers does not appear to have-obtained Staff approval with respect t'.o the engineering QA procedures

[

i which.it had followed (Tr. 5750).

Furthermore, Consumers seems to have a 4

4 tende'ncy'to treat as many structures.as possible as non-Q-listed (and, 2

hence, as not subject to QA controls)' (Tr.. 5626,5671-72).

For these reasons, we are not completely satisfied as to the e tent to l

which QA p\\lans and. controls are to be applied; by Consumers to underpinning activities.

In particular, we are concerned about areas adjacent to, but

}

not necessarily directly under, safety class structures.

These activities include boring of large diameter, closely spaced holes for soldier piles i

which would penetrate low shear-strength soil layers at elevations below the foundations of adjacent safety-class structures (Tr. 5674-79; $765-71), and essentially all underpinning activities beneath the turbine building the i

j failure or tilting of which might influence the safety or future seismic h

I ;

p I

l t.

... - -. ~ =

~

^

=

u-

~

4 I

t

- i resistance of the adjacent safety-class structures (Tr. 6083-85; 7125-27).

These potential QA/QC gaps lead us to believetthat, at least in the 'near i

future,, the comencement of safety-related activities of this type should be subject to the Staff's approval--particularly as to whether specific activities. are to be covered or ndt covered by ran appr'opriat'e QA l

I i

pl an.32./

I 1

IV.

Related Matters: Substantiating l

The Need for Interim Conditions j

n Certain matters which have been the. sub' ject of.' notifications by various f

parties to the Board tend to accentuate what we regard as the need for the I

I interim conditions we are imposing. These matters have not yet been~the subject of evidentiary hearings, and we express no final view as to their i

accuracy or import. Nonetheless, we regard these matters as closely 1 '-

relevant.to the facts on which we have takem evidence and pertinent to our determination that interim conditions:should. be imposed.

l As one example of this type, representing.an activity we believe should l

l be covered by the commitment, the Board has been informed by way of a s'

Consumers' Non-Conformance Report that a.42-inch diameter hole was drilled to a depth of 40 feet within the "Q"' fill area,. apparently without proper authority; without the development of, or adherence to, written procedures; i

i 32/ We understand that Consumers. later indicated that monitoring f

instruments would be placed before comencing underpioning activities to measure horizontal movements between the turbine building and adjacent structures "in response,to questions raised by the Atomic j

Safety and Licensing Board". Memorandum dated March 11, 1982 from Dari j

Hood, Sumary of March 8,1982 Telephone Conversation Regarding Soil l

Spring Stiffnesses for AuxiliaryiBuilding Underpinning and Phase II,

Construction.

e g

g I

.m

.e mm.r s w,m.

e. m e m a.oew" e

'~~

^-~

. :.s.. -. -' ~

1.. -.

~~

4.

c.

i j!

j; 17 i

without the participation of the On-Site Geotechnical Eng.ineer; and without g.

adequate QA/QC surveillance, if any.33/! We hasten to point out that

^ -

- we h* ave not yet heard evidence on this. report. and express no view as to its accuracy. It appears, however, to describe the. type of activity which is c

encorpassed by the prohibition: in*Part IV, Section 1(a) of the Modification

+

l Order. Moreover, if the NCR is accurate, the' activity would constitute a t

I

-prime example of the kind of work which we believe. should be subject to l

s 1

prior Staff review. and concurrence.

g Additionally, we have also recently been notified of loose sands located in the plant fill north of the Service: Water Structure and Circulating Water Intake Structure. This loose sand reportedly underlies about 500 feet of seismic Category I pipe.

We understand that Consumers j

4 I

has (fec,ided to remove and replace this: material to avoid potential liquef action problems.E Once again, we express no view as to the '

t validity of this information.

But considering. the vagueness as to the limits of' Consumers' comitment and the apparent potential effect on public safety of 4hese construction activities should the plant later be allowed to operate, we deem it necessary at this time to eliminate any uncertainty and 33/ NCR # M01-4-2-008 Rev.1, dated February 25, 1982, transmitted to the

~

Board and parties by letter dated March'12,1982, from James E.

Brunner, CPC.

The Board requested.that; it be provided with audit reports of this type (Tr. 5975-76).:

34/ Memorandum from Darl Hood, Notif.ication of Loose Sands Beneath

~

Service Water Piping, March 16, 1982.. See also letter from James W.

Cook to liarold R. Denton, Additional Information Concerning Safety j

Grade Buried Piping, March 16, 1982..

0

-9"-

e'

~

ga -

-a A---

v-->.

-,.y,,

pw,

,e-,-,_

g.,-

yn,,.,ypgew - p e-w g g4 99.,

,-,a_,.g.i_.,ey.,.9w.y e-,,-m-..

y 9e-s-.sg 9,,pw,--.+-y9.,,my,.%,..,

7 c.,,4-_,..,wga-

-.a-~.-

k 1

i i

to require that any remedial actions intendedito rectify this matter receive full Staff review and concurrence before being undertaken.

.I Finally, the Board notes that the :S$aff has disagreed with I

Consumers.El over the extent of QA coverage.and control of the 3

t I

underpinning activities beneath.(he safety-class and adjacent non-safety class bui1Dngs. The disagreement apparently.has been resolved by

, Consumers',uagreeing that essentially all underpinning activities would be

...e subject to Q-controls, except~ for certains already completed activities and l

certain agreed-upon non-critical activities _36/

I Although the Board recognizes that these disagreements may reflect genuine l

t differences of interpretation of requirements in Appendix 8 to 10 C.F.R. 50, l

we deem it important to public safety that, pending the completion of our QA l

review,g5taff's more conservative interpretation shouWapp remedfal work activites, some of which.are, or shortly will be, in ' rogress.

p

=

~

Accordingly we have made the elements of that agreement part of this Interim 4

Order. Again, white we express no views.as to the validity of those' matters brought t6'our attention outside the. actual hearings, they represent the i

kinds of issues that were alleged in the December 6,1979 Modification 3

35/ Memorandum dated March 12, 1982, from Darl Hood, subject:

Summary of March 10, 1982 Remedial Foundation Work. Meeting Concerning Quality Assurance To Be Applied To 36/ Letter, James W. Cook (CPC) to J. G. Keppler (NRC), dated April 5

~"-

1982, subject:

Quality Assurance for, Remedial Foundation Work.

l-O a

II

!3

~

.3

~

19 I

i j

Order, and that were the subject of ongoing; efforts by the Staff 'and 4

Consumers to,reso$ them.

3

[

V.

_ Description of Inter:im Requirements

.t As a result of the various safety problems which we have described in Section Ill, above, the potential-and related problems described in.Section

+-

IV, above, and the iminence of the.comencement of additional I

. safety-relaud work activities on remedial! measures for the soils settlement problems which we have been considering, we find it necessary to act now to i

3 remove ambiguities in Consumers' comitment to obtain prior Staff approval

' for remedial measures.

Pending the. completions of our review of the record and issuance of a partial initial decision, we are requiring that the construction permits be amended to prohibit, (.in the absence of Staff t

approval) the same activities as would.have been prohibited by Section IV of the Modification Order.

(We are updating the requirement to take account of certain developments which have occurred sincer December 6,1979.)

This

?

requirement would not apply to any of the activities as to which the NRC has already gi,ven its approval.

Nor does,it dictate the manner in which the Staff may exercise its review--1.e., whethen piecemeal (individual

~i construction steps) or as an integrated package.

In addition, for the reasons we have outlined, we are reqtriring that certain of these activities D

l e

9

• e i

n

==wa w.-

?

l**

l I,$

o 4

l.

i a

he governed by a QA plan.38,/ Wehavepointed.outthat$omeofthe t

material which: we haq considered in this. order has not yet been the, subject

[

\\

i of a completed evidentiary hearing; indeed,e the scope of our QA requirement i

r is premised in part upon an apparent agreement.between Consumers and the i

Staff contained in material of this sort.

Letter of James C. Cook,'fn. 36,

.a-We expect Consumers and the NRC' Staff.to present testimony on these supra.

open items at a later evidentiary session.

e4 I

We stress that in our forthcoming Partial Initial Decision we will i

l l

reexamine the terms and conditions which! we are. here imposing on an interim

• basis. At that time, we may reaffirm, expand.or remove them.

Until,such B

time, however, we find that the Modification. Order should be made effective to the extent which we have described. We stress that we are not at this tifne requiring the submission' or approval of any amendments to the y-applicati'ons, for constructio'n permits (as provided by the Modification Order).

In our opinion, the Staff consultation and approval which we are requiring will achieve the substantive results we believe necessary without adding certain procedural requirements of an application for a construction 4

s N

permit amendment:which, in the present context, do not appear to be necessary'to attain the safety goals which we believe should be achieved.

38f To r'equire a QA plan for safety-related. remedial soils construction activities is consistent with the requ.irements of 10 C.F.R.

$50.34(a)(7).

We note that the. large-scale underpinning and other remedial ~ activities which are being undertaken are sufficiently.

e distinct from the activities contemplated during the construction-permit review as to warrant a. supplementation of the applicable QA program.

h p'

i 1

l

...a

..u :. L. -

~

.~

e s o.

]'o

.}.

3

.- i j

21 _

i 4

l VI. Order Based ore the foregoing, it is,.this 30tiv day of April,1982 i

.' ORDERED t

That the Director of Nuclear Reactor Regu:1ation, in accordance with 10 i

t

~

C.F.R4 $2.764(b)', is authorized tb amend Construction Permits CPPR-81 and t

+

CPPR-82 as follows:

(1) Construction Permits CPPR-81 and. CPPR-82 shall be am i

ded to l

require that the permit holder obtain explicit prior approval l

from the NRC Staff (to the extent such approval has n6t v

already been obtained) before proceeding with the following soils-related activities, and.that these activities, with the l

exception of those already approved by the NRC, and those that 3

the Staff agrees are noticriticaJ, shall be controlled by a Staff-apn' raved Quality Assurance.P1an:

(a) any placing, compacting, excavating, or drilling soil

[

t materials around: safety-re-lated structures end systems;

~ _ _. -

(b) physical implementation: of remedial action for correction of soil-related problems under and around safety-related l

structures knd systems, including but not limited to:

I j

(1) dewaterinoi tystemo (ii) underpinning.of service water building (iii) removal and replacement of fill beneath the i

feedwater itoletion valve pit areas, auxiliary building electrical. penetration areas and control l

l tower, and. beneath> the turbine building

~

s.

o h

l

.m

..e.

.2

_. _._ j _._ _.._

- - -,cm -

e,.

v.

u I

. ~'..

.1 f.

22 ;

f.

s r

u l

1 I

g-(iv) placing of underpirining -;upports beneath Iny of *.

j ' ".

tne structures: listed in (iii) above i

i jj f-(y) compaction and: loading activities; I

[t.

(c) construction work in soil materials,under or around l

s x

}di*

safety-related structures. and systems such as field

] {;..,

t installation, or rebedding,.of conduits and piping.

(2) paragraph (1) above shall not applyeto remedial actions l

approved by the NRC Staff prior to the effective 'date of this Order, nor to any exploring, sampling, or. testing of soil 1

t samples associated withidetermining actual soil proper' ties on site which has the approval'of the Director of Region III, t

Office of Inspection and Enforcement. These testing l

activities, however, shal:1. be controlled by a Staff-approved 3

. s,

. Quality Assurance plan which. includes procedures for I

t i

controlling excavation or drilling activities more than 6-feet deep in "Q" areas.

(

~

In accordance with 10 C.F.P.. {l 2.760. 2.762, 2.764(a) 2.785 and f

6 2.786, thi's Memorandum and Order shall be effective tranediately upon I

t issuance and shall constitute. the final. action of the Commission on the matters considtree herein forty-five. (45) days after issuance, subject to any review pursuant to the above-cited Roles.of Practice.

Exceptions to this Memora'i1dum and Order may be filed by any party within ten (10) days after its service. A brief in support of the exceptions shall be filed within thirty (30) days thereafter (forty (AO) days in the case of the NRC Staff). Within thirty (30) days 'of the filing and service of the brief of i

I

~~

'~~

,,,. -.., -, - _ _. -. _,,. -.,,,..,_._._...._-,.v.____-_---.__my_y_,

_,~,._,y.._,.

~

,w.s g_-w

.,,-g,,. -

-w

_.w,,my

r

... +. ~..

g u.

f*.'

j J

t j'

23 -

i ii 8 74 -

the appellant (forty (40) days in the case. of the NRC Staff), any other o

party may fils a brief in support of, or in opposition to, the exceptions.

THE ATOMIC SAFETY AND LICENSING BOARD hehr es secnnowf er Cnayman~

i

~

~

+

a ADMINISTRATIVE JUDGE F

ll,

~

.e k

U q Dr. Frederick P. Cowan, hember ADMINISTRATIVE JUDGE t

I

~

j Ralpng.. Decker,Memoer ADMIh1STRATIVE JUDGE Dated.~at,Bethesda, Maryland o

L this 30th day of April, 1982.

i Judge Jerry Harbour, who has served as a technical interrogator and an alternate Board member during portions of the hearings concerning management attitude and quality assurance matters;.and who has replaced Judge Decker 2

for the forthcoming segments of the consolidated OL-DM proceeding (with the exception 'of the first Partial;Initia1' Decision and orders, such as this one, which are integral to that Decis. ion).. supports the rulings and reasoning, included'in this Memorandum and Order.

l.

?

I N

l M

s h

i e e 6

4 f

L l

1

.se..em-v'

• ~

n.

n

---..w

+

_,,,,,n.-

,.~,,-.a..w.

,,-m

+-

,e ja; 3

James W Cook Vice Pressdent - Protects. Engsneersng and Constructs,s oenerse Offices: 1945 West Perneff Road, Jackson. M. 49201 e 1517) 788 0453 April 30, 1982 V 1 nt qy.o._!, 0

~

DIP i

n!n b

^k'_--

Harold R Denton, Director 3

S Office of Nuclear Reactor Regulation Division of Licensing

_,',, 7

~

US Nuclear Regulatory Commission g-d

$o Washington, DC 20555 j

g MIDLAND PROJECT MIDLAND DOCKET NO 50-329, 50-330 EFFECTS OF CRACKS ON SERVICEABILITY OF CONCRETE STRUCTURES AND REPAIR OF CRACKS FILE: 0485.16 SERIAL:

16884

REFERENCES:

(1) J W COOK LETTER TO H R DENTON, EVALUATION OF FEEDWATER ISOLATION VALVE PITS AT MIDLAND PLANT, SERIAL 15493, DATED JANUARY 25, 1982 (2) J W COOK LETTER TO H R DENTON, EVALUATION OF AUXILIARY BUILDING CONTROL T0VER AND ELECTRICAL PENETRATION AREAS AT MIDLAND PLANT, SERIAL 15527, DATED JANUARY 29, 1982 (3) J W COOK LETTER TO H R DENTON, EVALUATION OF THE EFFECT ON STRUCTURAL STRENGTH OF CRACKS IN THE WALLS OF THE DIESEL GENERATOR BUILDING, 4

SERIAL 15978, DATED FEBRUARY 16; 1982 (4) J W COOK LETTER TO H R DENTON, EVALUATION OF CRACKING IN SERVICE WATER PUMP STRUCTURE AT MIDLAND PLANT, SERIAL 16009, DATED MARCH 2, 1982 ENCLOSURE:

EFFECTS OF CRACKS ON SERVICEABILITY OF STRUCTURES AT MIDLAND PLANT References 1 through 4 above transmitted a series of reports which presented an evaluation of the effect on structural strength of cracks observed in the feedwater isolation valve pits, the auxiliary building control tower and electrical penetration areas, the diesel generator building, and the service water pump structure. These four rep >rts were provided as the result of discussions with the NRC Staff and its consultants at meetings held on December 10, 1981 and January 11, 1982. During these meetings, Consumers Power agreed to provide the NRC with an evaluation of the effects of cracks on the longterm serviceability of concrete structures and with recommendations on the sealing of cracks.

In response to this commitment, we are providing the enclosed report entitled,

" Effects of Cracks on Serviceability of Structures at Midland Plant," by Messrs W G Corley, A E Fiorato and D C Stark of Construction Technology oc0482-0085a100 C),

C m

y C L O ?-

MAY 5 1982

- - - o

_w /

f.

=~ '-

~ ~ ~ "

~

1

)

2 4.-

Laboratories, a division of the Portland Cement Association.

This report contains a discussion of the effects of observed cracks on the serviceability of the feedwater isolation valve pits, the auxiliary building, the diesel generator building and the service water pump structure and provides our recommendations for the sealing of cracks in these structures.

Please note that the enclosed report does not apply to the borated water storage tank foundations.

The repair of cracks by pressure grouting of the borated water storage tank foundations has been addressed in a seperate 50.55(e) report forwarded to the NRC by our recent correspondence, Serial 16172, dated April 23, 1982.

Based on the conclusions reached in the enclosed report we wish to recommend the following:

(1) sealing of cracks in walls by epoxy injection for cracks above the permanent water table is considered unnecessary; (2) sealing of cracks by means of epoxy injection or other means for walls below the permanent water table, which show visible leakage of water, will be performed; and (3) the south wall of the service water pump structure will be coated on the exterior surface within the splash zone area adjacent to the cooling pond a

i.e., between Elevation 626' and Elevation 637.5'.

The epoxy injections can be applied from the interior surface.

We are also advising that the work to seal cracks will be performed after completion of the underpinning operations.

JVC/RLT/FV/mkh e

/

s CC l

Atomic Safety and Licensing Appeal Board, w/o CBechhoefer, ASLB, w/o MMCherry, Esq, w/o FPCowan, ASLB, w/o g

I RJCook, Midland Resident Inspector,.w/o RSDecker, ASLB, w/o SGadler, w/o l'

JHarbour, ASLB, w/o GHarstead, Harstead Engineering, w/a DSHood, NRC, w/a (2)

DFJudd, B&W, w/o JDKane, NRC, w/a FJKelley, Esq, w/o RBlandsman, NRC Region III, w/a WHMarshall, w/o JPMatra, Naval Surface Weapons Center, w/a WO'tto, Army Corps of Engineers, w/o WDPaton, Esq, w/o SJPoulos, Geotechnical Engineers, w/a FRinaldi, NRC, w/a HSingh, Army Corps of Engineers, w/a BStamiris, w/o oc0482-0085a100

r f

Report to CONSUMERS POWER COMPANY JACKSON, MICHIGAN EFFECTS OF CRACKS ON SERVICEABILITY OF STRUCTURES AT MIDLAND PLANT by W. G. Corley, A. E. Fiorato, and D. C. Stitrk Submitted by CONSTRUCTION TECHNOLOGY LABORATORIES l

A Division of the Portland Cement Association t

l 5420 Old Orchard Road Skokie, Illinois 60077 April 19,1982

(

r >~ v^ t /j n

rs m&va 6

t 4

4 1

TABLE OF CONTENTS Pace No.

INTRODUCTION.....................

1 OBSERVED CRACKS IN MIDLAND PLANT STRUCTURES 3

DURABILITY OF CONCRETE STRUCTURES AT MIDLAND 5

Freezing and Thawing.

6 Chemical Attack 7

Corrosion of Reinforcement 10 RECOMMENDATIONS FOR REPAIR,.

13

SUMMARY

AND CONCLUSIONS 16 REFERENCES 18 l

8 L

l

-i-i construction technology laboratories L

F g, mas

• +N

• ne

#^

D

-T

m h

1 p

EFFECTS OF CRACKS ON SERVICEABILITY OF STRUCTURES AT MIDLAND PLANT by U. G. Corley, A. E. Fiorato, and D. C. Stark *

?

INTRODUCTION A series of previous reports have presented an evaluation

+

of the structural significance of cracks observed in the Feedwater Isolation Valve Pits, Auriliary Building Control Tower and Electrical Penetration Areas, Diesel Generator l.

Building, and Service Water Pump Structure at Midland Nuclear 4

Power Plant Units 1 and 2.II'4)**

Observed cracks in these structures were described and the significance of the cracks a

with regard to future load carrying capacity was discussed.

A site plan for the Midland Plant, which indicates buildings evaluated, is shown in Fig. 1.

This report contains a discussion,of effects of observed cracks on serviceability of the structures evaluated.

Primary emphasis is given to durability of the concrete structures ov'er their service life.

Recommendations for repair of selected areas are also made.

a

• Respectively, Divisional Director, Engineering Development Division; Director, Construction Methods Department; and Principal Research Petrographer, Concrete Materials Research Department, Construction Technology Laboratories, a Division of the Portland Cement Assrciation, 5420 Old Orchard Road, Skokie, Illinois 60077.

• • Numbers in parentheses refer to references listed at end of this report.

the l I..

ConstrUCalon technology 13bormforl0$

~

r e

r w-g

,~,y>+v.,,-

gr' - -

w'

t TITTABAWASSEE RIVER 1

COMBINATION\\

SHOP EVAP AND M

N AUX BOILER ~

BLDO k

I 80 RATED WATER O

TANK COOLING TOWER O

SOLID R ADWASTE

{

AUX BLD

,j REACTOR mLDO 0

I 7

UNIT 1 REACTOR BLDG O

UNIT 2 ADMIN S T N AND-*

CONTROL TOWER SERVICE WATER

, PUMP STRUCTURE DIESEL GENERATOR

=E DLDG s,__

,'w IRCULATING WATEM O

INTAKE STRUCTURE N

s OE

'\\

%s' i

\\

s

[

EMERGENCY COOLING

\\

\\

WATER RESERVOIR

\\

AFFLE DIKE *s

___,,,,,,,/

t sm*u COOLING POND FIG. 1 SITE PLAN l

2.. -.

r-

~ -. -.

{

OBSERVED CRACKS IN MIDLAND PLANT STRUCTURES Cracks observed in the Feedwater Isolation Valve Pits and the Auxiliary Building Control Tower and Electrical Penetration i

Areas of Midland Plant Units 1 and 2 were primarily attributed to restrained volume changes that occurred during curing and

' drying of concrete.

Cracks observed in the Diesel Generator Building were attributed to restrained volume changes, and reported differential settlement between duct banks under the building and the, north and south portions cf the building.

{.

Cracks observed in the Service Water Pump Structure were attri-

[

buted primarily to restrained volume changes although the 1

occurrence of settlement related cracking could not be entirely 4

dismissed.

i In terms of future serviceability of these structures, and potential problems with durability, cracks located in exterior exposed surfaces would be expected to have the most significant influence.

This is because exposure conditions for' exterior j

surfaces are more severe dhan those for interior surfaces.

)

Maximum reported crac( width in exterior surfaces of structures investigated at Midland was approximately 0.025 in

However, most observed cracks were significantly smaller than this maximum value.

The fact that observed crack widths were spread n

over a wide range is consistent with most observations of crack-r e.

y';

ing in concrete members.

Crack widths are inherently subject to wide scatter.I ' }

,r American Concrete Institute Committee 224 lists " tolerable crack widths" for reinforced concrete me'mbers as a function of l-

. {:

b construction technology laboratories 5

l uv av "

" ' " ~

9-M; y

y

__.4 y-

---m-m--ut

---'"-*'-rm'aw'9-+7

' * " -"T

.:_ w-

. - ~

• e a

R l

different exposure conditions. (6)

For interior members, a

" tolerable crack width" of 0.016 in, is listed.

For exterior members subject to humidity, moist air, or in contact with soil, the " tolerable crack width" is listed as 0.012 in.

ACI Committee 224 emphasizes that "it should be expected that a portion of the cracks in the structure will exceed these values by a significant amount."(6)

Committee 224 also notes that

~

their tabulation of width limits "is a general guide for toler-able crack widths at the tensile face of reinforc $ concrete structures for typical con

• itions and is presented as an aid to d

(

be used during the design process."(6)

The crack widths are related to service conditions.

The presence of crack widths in excess of selected tolerable values occurs because crack limits can only be related to equa-tions that predict probable" maximum widths. (6)

Although

+

this probable value usually means that approximately 90 percent of crack widths in the member are below the calculated value, n

~

isolated cracks in excess of twice the width of the computed maximum can occur. (6)

Research data also ind'icate that the range in randomness of crack widths incr' eases with size of member.(6)

It should also be noted that equations for evaluating crack widths of flexural members are related to instantaneous or short term loading.

Volume changes related to shrinkage, creep, or temperature and humidity variations, are not taken into account.

For beams under nominally constant loading, research data have shown that crack widths can increase significantly with time. (7)

~4-

)

l construction technology laboratories 2

~

,n_.

4.

~'~ -

-a-

.t 4

i

\\

Thus, the maximum width would not be expected to remain constant 4

after a crack initially forms.

Therefore, in evaluating cracks in an existing structure, tolerances developed for design can not be arbitrarily applied.

For structures evaluated at the Midland Plant, most of the cracking, and crack growth, related to restrained volume changes should have taken place since construction was completed.

Future movement of cracks related to normal volume and temperature a

changes should not affect conclusions developed in this report.

.However, cracks that may develop as a result of unanticipated settlement or from underpinning operations should be evaluated to determine their effects.

The need for repair of such cracks can only be determined after their significance has been eval-uated.

Evaluation of such cracks has been included as part of the " Recommended Program for Monitoring Structural Integrity" of Midland Plant structures.

~4I Based on the above discussibn, crack widths observed in structures investigated at the Midland Plant are judged to be within the range implied by published tolerable crack width limits.

~

DURABILITY OF CONCRETE STRUCTURES AT MIDLAND This discussion covers durability of concrete as related to structures investigated at the Midland Plant.

Emphasis is given to durability questions relevant to observed cracks in the Feedwater Isolation Valve Pits, Auxiliary Building. Control Tower i

and Electrical Penetration Areas, Diesel Generator Building, t

i i

and Service Water Pump Structure.

Prior to dicrussing specific l

)

~ construction technology laborstories I

e 6

-~

r f

~ '""

-..._ u.. _...

u..__

}-

I measures for each structure, a basic discussion of durability of a

concrete structurer is presented.

Durability of concrete is defined as "its ability to resist weathering action, chemical attack, abrasion, or any other pro-cess of deterioration."IO'9)

With regard to questions of potential durability problems in Midland Plant structures, three types of concrete deterioration were considered:

freezing and thawing, chemical attack, and corrosion of reinforcement.

4 Freezing and Thawing Although the actual mechanism is quite complicated, freeze-U thaw damage is basically caused by expansion a,nd diffusion of freezing water in the pore system of cement paste and aggre-ga tes. (8,9,10)

Freeze-thaw cycles cause progressive deterioration as a result of continued expansive pressures from excess water that freezes in concrete.

Since freeze-thaw deterioration requires the presence of absorbed water that can be frozen, the occurrence of freeze-thaw deterioration on vertical surf aces is rare.

Resistance to freeze-thaw damage is obtained by designing structural members to minimize exposure to moisture, by using concrete having low in-place permeability, by using a low water-cement ratio, by using air-entrainment, and by using sound aggrega tes. (8,9,10)

Concrete with low permeability does not absorb as much water which can later freeze.

According to information provided by Bechtel, concrete mixes

\\

used in walls of the buildings investigated at the Midland Plant had water-to-cementitious material ratios ranging from 0.41 to

, construction technology laboratorres

' " ' ~

~

. a., a,. :." -----..

~ -

~.

E i -

0.47.

These ratios are within the limit of 0.50 recommended by American Concrete Institute Committee 201 for concrete resis-tance to freeze-thaw damage. (8)

In addition, since exterior exposed surfaces in walls of tile structures are unlikely to collect or transmit water, occurrence of freeze-thaw damage is judged to be unlikely.

It is not expected that cracks of the type observed in the inspected structures would have potential to collect and retain water.

Chemical Attack Dry concrete does not react with dry chemicals. (8,9)

For deterioration to take place, chemicals must-be in solution and in sufficient concentration to provide an aggressive environ-ment.(8,9)

Although buildings are exposed to a number of potentially corrosive chemicals under normal environmental and atmospheric conditions, concretes generally resist chemical attack from normal conditions of exposure.

American Concrete Institute Committee 515 has prepared detailed tables on effects of chemicals on concrete. (11)

General types of chemical attack include acid or alkali attack, or sulfate attack.

4 Concrete's resistance to chemical attack is dependent upon the type and concentration of the chemical solution in contact with the conctate, the temperature and pressure of the solution, and the quality of the concrete.I9)

Deterioration of concrete by acids is primarily the result of the reaction of acids with calcium hydroxide in the hydrated portland cement paste. (8,11)

This results in the formation

-7.

Construction technologylaboratories

-.2-,

~

,4

-m

• WT

p _ w _.

t.

I l, '

of water-soluble-reaction products and subsequent disintegra-tion of the concrete.

Strong alkaline solutions (over 204) attack other ' constituents in the hardened paste to cause I,

disintegration. (8,11)

Sulfate attack results from complex chemical reactions between sulfate solutions and constituents of hydrated portland cement paste that result in expansive a

compounds which cause progressive disintegration of concrete. f 8,11) 3 In all cases the rate of chemical attack is more rapid in warmer clima tes. (8-ll)

Conditions at the Midland Plant suggest the following hypo-4 thetical situations as being conducive to chemical attack:

1.

Highly concentrated acid solutions in the cooling pond that could attack concrete in walls of the Service Water Pump Structure.

2.

High sulf ate contents in the soil, in the cooling pond, e

or in groundwater adjacent to the concrete structures.

3.

Atmospheric pollution that could, in combination with moisture, form " acid rain."

?

According to Michigan MPDES Permit Application, Amendment 3, dated September 30, 1981, the pH* level of the cooling pond water can range from 7.0 to 9.0.

This pH level can be compared to that of potable groundwater which has a pH of approximately 7.0.

Seawater has a pH range from 8.0 to 9.0 Thus, pH levels of the cooling pond water are not unusual.

[

• The pH value of a solution is a measure of its acidity on j

basicity.

A neutral solution, or pure water, has a pH of 7.

f Stronger acids have lower pH values. (9)

!. L construction technologylaboratories L

2

.- rL. ~

^'

T *

--~

- - ~ "

With regard to sulfate attack, no unusual levels of sul-f ates in suils or groundwater at the Midland Plant hs.ve been reported to Construction Technology Laboratories staff.

Sulfate levels in the cooling pond are listed in the Michigan MPDES Permit Application, Amendment 3, dated Sept. ember 3C,1981.

According to the permit, sulfate levels can reach maximum values of 908 mg/l (908 ppm of SO ).

This compares to values of 2500 4

to 3000 mg/l of sulfate present in seawater.

Potable ground s

water has a sulfate level of approximately 30 mg/1.

American Concrete Institute Committee 201 considers sulfate r

[

levels in water of 150 to 1500 mg/l as a " moderate exposure"

. condition, and recommends a maximum water-cement ratio of 0.50 for this exposure condition.

As mentioned previously, struc-tures at the Midland Plant have water-to-cementitious material ratios of 0.41 to 0.47.

These ratios are below the limit recom-mended by ACI Committee 201.

Committee 201 also recommends that Type II cement be used for " moderate exposure" conditions.

According to Bechtel, Type II cements.were used in concretes for the structures evaluated.

Therefore, the structures should have adequate resistance to sulfate attack.

Generally, air pollution severe enough to cause daaage to concrete structures would not be tolerated on the basis of environmental concerns.

Therefore, it is not anticipated that external walls which are exposed to the atmosphere at the Midland Plant would be susceptible to any more damage than would occur in any concrete structure located in a similar environment. CortSt!UCtiorf itChnology 13OC'3 tories

~ ~ ~

p With regard to concrete's resistance to chemical attack, the presence of cracks would expose more surface area to chemi-cal solution.

However, considering the exposure conditions and concrete quality for structures at the Midland Plant, it is con-cluded that chemical effects would not be any more severe than for other concrete structures in the area.

Corrosion of Reinforcement Concrete normally provides a high degree of corrosion pro-tection for embedded reinforcement. (8,0 This protection occurs because high alkalinity of the concrete provides a passive environment for the steel.

In addition, air dry con-crete provides a relatively high electrical resistivity which helps to resist corrosion. (8)

Corrosion of reinforcing steel is considered to be an electro-chemical process.(8,9)

Electrochemical corrosion results from flow of electric current and accompanying chemical reactions within the concrete.

Flow of electric current can be induced by stray electrical currents, by contact between different metals in concrete, or by differential concentration cells that may develop within the concrete.

The principal type of electrochemical corrosion in concrete structures -occurs as a result of corrosion cells that develop within the concrete and steel. (8)

Normally corrosion is prevented because a passive iron oxide film forms on the surface of the steel.

1 This film occurs in the presence of moisture, oxygen, and water-soluble alkaline products formed during hydration of cement.

However, the construction technology laboratories i

y

.--er**

i passive film can be destroyed if the alkaline environment of the concrete is lost.

Reduction in alka'linity can occur by carbonation of the hydrated portland cement or by ingress of chloride ions in the presence of oxygen. (8,9)

Penetration of oxygen and chloride ions through concrete can result in corro-sion cells being formed.

The cells form when anodic and cathodic areas develop along steel reinforcement because of differences in moisture content, oxygen concentration, and chloride ion concentration. (8)

Corrosion is initiated at anodic areas on reinfor' cement.

Since products of corrosion

(" rust") take up a larger volume than the original steel, expansive forces are eventually gen-erated as corrosion becomes severe.

These forces can cause cracking and spalling.

Primary elements essential for electro-chemical corrosion in reinforced concrete are:

1.

Presence of an electrolyte 2.

Presence of oxygen,

• J An electrolyte is a solution capable of conducting electric

• , current by ionic flow.I0I For example, moisture and chloride ions will form an electrolyte capable of conducting a

" Corrosion current."

Generally, steps taken to prevent corrosion are related to providing a low permeability concrete with adequate cover over reinforcing steel.

While it would appear that presence of cracks in concrete structures would increase risk of corrosion, no conclusive evidence has been found to indicate that any rela-tionship exists bitween crack widths and corrosion. (12)

It N,

COnstruCllon itChnolO{Fy 13bOf8tOnt$

~'

^ ~~

~-~r a

w--r

l

\\

has been found that cracks with widths less than 0.06 in., which run approximately transverse to the direction of reinforcing steel, have little influence on corrosion. (8,12)

A greater risk of corrosion occurs from cracks that run along the line of the reinforcing bar. (8,12)

For structures investigated at the Midland Plant, it is not anticipated that corrosion would be a problem with regard to future durability.

The presence of cracks in exterior wall surfaces above grade will have little effect on corrosion

-because these areas are not subject to moisture conditions con-ducive to corrosion damage.

The same is true for walls that are below grade level but aoove the water table.

For walls below the water table and for the south wall of the Service Water Pump Structure adjacent to the cooling pond, the potential does exist for build up of chloride ions as a result of alternate wetting and drying of concrete.

It should be noted that the chloride level in the cooling pond adjacent to the Service Water Pump Structure is relatively low.

According to the Michigan MPDES Permit Application, Amendment 3, dated September 30, 1981, chloride (C1) concen-tration in the cooling pond can reach a maximum of 425 mg/1.

This concentration can be compared to the level of chloride in seawater which can be 19,000 mg/1.

Potable ground water would have chloride levels of approximately 20 mg/1.

Thus, the cool-ing pond environment is not severe.

However, as a precaution against possible build up of chloride ions in the splash zone t construction technology laboratories

--$s.W

~ ~ ~--~

~ ~

of the cooling pond, it is recomme'nded ti.st this area of the wall be coated to prevent possible ingre's of chloride.

s The Michigan MPDES Permit Application also indicates that the pH -level of the cooling pond water can range from 7.0 to 9.0.

This pH level can be compared to that of seawater which ranges from 8.0 to 9.0 and that of potable groundwater, which is approximately 7.0.

The pH level in the cooling pond water-is not considered to be low enough to severely reduce the alkaline environment.that the concrete provides for rein-forcement.

RECOMMENDATIONS FOR REPAIR Epoxy injection of existing cracks above the water table in the Feedwater Isolation Valve Pits, the Auxiliary Building Con-trol Tower and Electrical Penetration Areas, the Diesel Generator Building, or the Service Water Pump Structure is not required to ensure future structural integrity.

Epoxy injection would have no influence on capacity of these structures since the existing cracks are not detrimental to capacity.

Although epoxy injection would increase overall stiffness of the cracked structures, it is unlikely that original stif fness would be recovered, (13) nor is it necessary to recover the original stiffness.

Epoxy injection of existing cracks in exterior and interior walls above the water table is not considered essential to ensure durability of the structure.

Freeze-thaw damage is not considered likely in the walls because the vertical surfaces l

provide adequate drainage to prevent water from being trapped.

13-i5 construction technology Isboratories w

-.m s-,

,,.,,-m

,ww.

n, p

Q mm.

,,,g ppp.--,,-,,,

wa

,.,, -,,e

m 1_ _ _ _

I' Freeze-thaw deterioration does not occur in unsaturated con-crete.

In addition, atmospheric exposure conditions at the Plant are not reported to be unusually severe.

Therefore,

- deterioration from chemical attack is not anticipated.

Finally, I

in the absence of chloride ions, the alkaline atmosphere at the level of the reinforcing bars will prevent damage from corrosion in walls above the water table.

For cracks in walls below the water table, epoxy injection or other means of stopping leakage is recommended.

This recom-

.mendation represents a precautionary measure against possible durability problems that could result from a gradual build up of chlorides or sulfates as concrete is subjected to repeated wetting and drying.

Epoxy injection can be applied from the interior surface.

Only cracks with visible signs of leakage, need to-be injected.

A water insensitive epoxy system should be used.

General guidelines on epoxy injection have been reported by American Concrete Institute Committee 546.I14I It is recommended that a surf ace coating be applied to the exterior of the south wall of the Service Water Pump Structure.

This coating should cover the splash zone area of the wall adjacent to the cooling pond.*

This recommendation is a pre-cautionary measure against possible corrosion problems that

• It is reported that the water level in the south cells of the Service Water Pump Structure is maintained at the same eleva-tion as the cooling pond.

Since conditions in these cells are not conducive to repeated wetting and drying, as in the exterior splash zone, coating of interior walls is not considered necessary. '

COnstruClion itChnology R&boralOrles L

~ ?

'? ~

_ _ ~ ' ~ '.___,.,_ ~ ~ ~ ~

. ~ '

~

_,A,__...-_.

s

---..--u.

~

^

~

j could' result if a gradual build up of sufficient chloride ion occurs as the concrete adjacent to the cooling pond is subjected to repeated wetting and drying.

The coating will restrict ~

ingress of chloride ions carried by the cooling pond water.

The. splash zone can be generally defined as the portion of wall subject to repeated wetting and drying.

According to the Midland Plant Final Safety Analysis Report, Revision 33, dated April 1981, the maximum operating water level in the cooling pond is at elevation 627 ft.

The minimum level is at elevation 618 ft.

The minimum level is based on a 100-day drought with no straam withdrawals made from the Tittabawassee River.

Thus, the i

minimum level would not be reached under normal conditions.

The normal operating level of the cooling pond ranges from elevation 626 ft to elevation 627 ft.

It is recommended that the exterior surf ace of the entire width of the south wall be coated between elevation 626 ft and elevation 637.5 ft.

This will provide protection from chloride build up caused by repeated wetting and drying under normal operating conditions.

Peformance criteria for the coating material include:

4 1.

The coating material should cover cracks i

2.

The coating material should have a low enough modulus to permit natural movement of cracks 3.

The coating should be able to withstand the range of environmental conditions that can be encountered at the site 4.

The coating should be water resistant

!* 4 construction technology laboratories

• .e""MW"'

_.m-

p~l

.2

. - - -. ~

5 5.

The coating should bond to damp concrete 6.

The coating material should resist debonding from moisture movement or vapor pressure within the wall 7.

The coating should exhibit long-term stability 8.

The coating should not react with chemicals in cooling.

pond water According to manufacturers' data, the following coatings are considered suitable for the intended application:

1.

Rubberstone Hi-Fill Fibrated.

United Coatings, Inc.

1130 E. Sprague Avenue Spokane, Wash.

99202 2.

Acuaflex Dural International Corp.

95 Brook Avenue Deer Park, N.Y.

11729 3.

Sika-Too 144 Sika Chemical Corp.

Box 297 Lyndhurst, N.J.

07071 Other suitable coatings may.be available.

American Concrete Institute Committee 515 provides recommendations for use of waterproofing barrier systems on concrete.Ill)

It is recommended that repairs be made after completion of underpinning operations.

SUMMARY

AND CONCLUSIONS

'This report presents a discussion of observed cracks in the Feedwater Isolation Valve Pits, Auxiliary Building Control Tower and Electrical Penetration Areas, Diesel Generatdr Building, and Service Water Pump Structure located at Midland Nuclear Power i

)

construction rec nnology taboratories o

--.,a

%~-waise*h*-*

~*

Plant Units 1 and 2.

Effects of observed cracks on future durability of the structures are discussed.

Observed cracks in walls above the water table are not expected to have a significant influence on future durability of the structures.

Therefore, epoxy injection of these cracks is not considered necessary.

For cracks in walls below the water table, it is recommended that epoxy injection or other means be used to stop leakage.

This precautionary measure is intended to prevent possible corrosion problems that could result from gradual build up of chloride ions.

It is also recommended th t the south wall of the Service a

Water Pump Structure be coated within the splash zone area adjacent to the cooling pond.

The coating represents a precautionary measure against possible corrosion problems that could result from gradual build up of chloride ions.

It is recommended that repairs be cade after completion of underpinning operations.

Epoxy injection of existing cracks is not required to ensure

~

future structural integrity. construction tecnnology tekorstories

._:m_.m W"

~

a_

. _ :_ _:nc._ :. _ =

u m2 m

1:

REFERENCES Corley,' W. G.. and Fiora to, A. E.,

1.

" Evaluation of Feedwater Isolation Valve Pits at Midland Plant," Report to Consumers Power Company, Construction Technology Lab-oratories, a Division of the Portland Cement Association, Skokie, Illinois, January 1982, 24 p. + Appendix.

2.

Corley, W. G. and Fiorato, A.

E., " Evaluation of Auxiliary Building Control Tower and Electrical Penetration Areas at Midland Plant," Report to Consumers Power Company, Construction Technology Laboratories, a Division of the Portland Cement Association, Skokie, Illinois, January 1982, 44 p. + Appendix.

3.

Corley, W. G. and Fiorato, A.

E., " Attachment 4 -

Evaluation of Cracking in Diesel Generator Building at Midland Plant," Report to Consumers Power Company, Construction Technology Laboratories, a Division of the Portland Cement Association, Skokie, Illinois, February 1982, 3,4 pp.

4.

Corley, W. G. and Fiorato, A.

E., " Evaluation of Cracking in Service Water Pump Structure at Midland Plant," Report to Consumers Power Company, Conctruction Technology Lab-oratories, a Division of the Portland Cement Association, Skokle, Illinois, February 1982, 40 p. + Appendix.

5.

Kaar, P.

H., "High Strength Bars as Concrete Reinforce-ment, Part 8.

Similitude in Flexural Cracking of T-Beam Flanges," Portland Cement Association Development Department Bullctin D106,1966, 11 pages.

6.

ACI Committee 224, " Control of Ccacking in Concrete Structures," Concrete International:

Desion and construction, Vol. 2, No. 10, October 1980, pp. 35-76.

7.

Roshore, E.

C., " Tensile Crack Exposure Tests.

Results of Tests of Reinforced Concrete Beams, 1955-1963,"

Technical Memorandum No. 6-412, U.S. Army Engineer Water-ways Experiment Station, Corps of Engineers, Vicksburg, Mississippi, November 1964, 21 pages.

ACI Committee 201, " Guide to Durable Concrete," Journal of the American Concrete Institute, Vol. 74, No. 12, g

Dec.

1977, pp. 573-609 ro p

9.

Woods, H., Durability of Concrete Construction, American p

Concrete Institute Monograph No. 4, American Concrete h

Institute, Detroit, 1968, 187 pages.

l l'

l l

l i._ I' construction technology laboratories 4

~ws**

e-

-,--w a

m en-!

r w!!

~.m, w----.I

-f 3

g;-

.w, p-- - * *

. : =-.

= = :.

l

..-.2

\\

10.

Neville, A'.

M., Properties of Concrete, Pitman Publishing, New York, 1975, 687 pages, q

11.

ACI Committee 515, "A Guide to the Use of Waterproofing, Dampproofing, Protective, and Decorative Barrier Systems for Concrete," ACI 515R-79, American Concrete Institute, Detroit, 1979, 41 pages.

12.

Beeby, A. W., " Corrosion of Reinforcing Steel in Concrete and Its Relation to Cracking," The Structural Engineer, Vol. 56A, No. 3, March 1978, pp. 77-81.

13.

Iliya, R. and Bertero, V.

V., " Effects of Amount and Arrangement of Wall Panel Reinforcement on Hystereic Behavior of Reinforced Concrete Walls," Report No.

UCB/EERC-80/04, Earthquake Engineering Research Center, University of California, Berkeley, February 1980, 156 pages.

14.

ACI Committee 546, " Guide for Repair of Concrete Bridge Superstructures," Concrete International: Desion and i

Construction, Vol. 2, No. 8, S,eptember 1980, pp. 69-88.

!i 1

4 i-

l construction technology Issorstories i

. _. _. ~.

~-

-.I

~*

~ '~~ '^

~ ~