ML20127A834

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Forwards Draft Response to Congressman Long Re Base Mat Problem in Response to Action Control Item 13324.IE Concurs W/Draft Response
ML20127A834
Person / Time
Site: Waterford Entergy icon.png
Issue date: 08/05/1983
From: Jay Collins
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To: Dircks W
NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
Shared Package
ML19263A633 List:
References
FOIA-84-455, FOIA-84-A-56 NUDOCS 8308180629
Download: ML20127A834 (10)
v • d • e


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SUBJECT:

RESPONSE TO CONGRESSMAN G. W. LONG - RE: WATERFORD-3 '

(50-382)

Attached is a draft risponse to Congressman Long co'ncerning the base mat problem at Waterford. This is in response to Action Control Item No. 13324.

The Office of Inspection and Enforcement has reviewed this draft response and have given their co.ncurrence. One : ,,.. of' I'i.d .. V .::.';

. . I John T. Collins Regional Administrator

Attachment:

Draft Itr to G. W. Long CC:

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The Honorable Gillis W. Long

  • United States House of Representatives Washington, DC 20515* .

Dear Congressman Long:

' Your letter of July 6,1983, regarding the cracks in the common foundation mat at the Waterford Steam Electric Station, Unit 3, has been forwarded to me for action. I am pleased to provide you the following information.

There have been two incidents of water seepage through the common foundation mat at the Waterford 3 nuclear facility. . The first occurrence was identified and the Nuclear Regulatory Commission was notified in July 1977. The location of the water seepage was.in the area where the concrete which supports the containment vessel was to be placed. The sealing and repair of the cracks

- was considered necessary by the licensee's architect-engineer before placing the containment support concrete, because the water could have been detrimental to the newly placed concrete. A method of repair was determined and the_ cracks were satisfactorily sealed and repaired. NRC Region IV inspected the corrective actions and concluded that the cracks were

'satisfactori-ly repaired.

A second occurrence was reported in May 1983 when a series of leaks were discovered in a different location. This event was documented in a noncompliance report and the NRC was notified. The cracks were identified by the observation of a small amounts of water percolating through the top of the mat at several locations.

Engineering st'udies were conducted by Ebasco, the architect engineer, to determine if any detrimental or deleterious effects could result from wah r seeping through the 12-foot steel reinf.orced concrete mat. These studies .-

examined the stability of the containment vessel against flotation and overturning under bouyant conditions caused'by postulated groundwater .

intrusion, by groundwater induced corrosion of the reinforcing steel and the containment' vessel, and by any effect en the base mat structural integrity due to groundwater percolating through the mat.-

Our NRC inspectors are currently monitoring the recent leakage and reviewing the studies. The cracks are not visible to the naked eye and are evidenced only by the moist spots on the unpainted floor, and by imperfections on painted surfaces.

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The Honorable Gillis W. Long .

As a result of recent anonymous concerns, NRC has initiated an independent inquiry to determine if the indications have been properly evaluated. We have also learned that Lousiana Power & Light has hired an independent consultant to review the significance of the leakage. A report on this independent review is scheduled to be available September 1,1983.

I trust that this inform ^ation is responsive to your request. We will provide you the results of the: ongoing studies and our conclusions when they become available. If you have any additional questions or require additional informa-tion, we would be pleased to discuss them with you. l Sincerely, N

- . William J. Dircks Executive Director for Operations 4

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t. ACTION CONTROL

' ' OATES CONTROL NO.

Rep Gillis Long 7/28/83 13324 OATE C# DOCUMENT m 7/6/83 PREPARE FOR SIGNATURE N nNAL REPLY OF:

FILE LOCATION 0" " *"

EXECUTIVE DIRECTOR OTHER -

E h LETTER O wEuo O REcoRT O OTHER SPECIAL INSTRUCTIONS OR EMARKS

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Encloses ltr Da Ronald H. & Carol B. la Burch concerning Waterford 3

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NRC SECRETARIAT o.ie '

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p,,,,. Ronald Burch

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To.

subject:

cracked slab--Waterford 3 4

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ADra.t.iSTFATret AssisiA*.?

Elasfjington, D.C. 20515

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b 1.!EMORANDUM TO THE OFFICE OF CONGRiiSS10NAL Rl!LATIONS

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Enclosed is a copy of a letter I recently received from one of my. constituents which concerns a matter under the jurisdiction of your agency. ,

I would L. most grateful for your advice and assistanee concerning the attached communication. Should you require any additional information, please call h'illiam hieaux of my staff at (202) 225-4926. .

Thank you very much.

GILLIS LONG MEMBER OF CONGRESS Eighth Congressional District Louisiana I' . . . . . . . . _ _ _ _ - - _ _ _ _ _ - _ _

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Dear Concerned Public Officer:

Would you want's nuclear power plant with a

. cracked slab in your neighborhood? We don't and we don't think you would either. Waterford

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3 has a cracked slabt Will the slab crack and~ result in a Louisiana disaster? Even a low probability is:too high a possibility.

Once Waterford 3 is fueled, the consumer will be assigned the responsibility for paying for.

!Waterford 3, cracked slab and all. They could be paying for their own destruction.

If.the~ crack in the slab propagates, the plant will-have to be shut down. Then the customers of LP&L will have to pay'not only for the construction, but also for the dismantling

. of Waterford 3 Why should the customer have to pay for the mistakes of LP&L management? ,

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STOP WATERFORD 3 NOW, before it is fueled.

Avert the physical or financial disaster that

, is sure to follow. Let LP&L pay for its manage-L ment mistakes.

Sincerely, .. , .

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DATES CONTROL NO. , x, ACTION CONTRCL .

FROM;.g 1also

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6 Sen. J. Bennett Johnston DATE OF DOCUMENT \p

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  • Encl'oses ltr ftn Ronald & Carol Burch L concerning cracked slab at Waterford 3 .

I as.o no to cars. mroa.91o. nourno Rpn incoming with reply.

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' ~ EXECUTIVE DIRECTOR FOR OPERATIONS NRC FORM 233 Hot PRINCIPAL CORRESPONDENCE CONTROL) V

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NRC SECRETARIAT .

s TO: Commissioner Date XX E noe. Dir./Oper. -

O cen. Coun ei .

Cong. Liaison Solicitor .

Public Affairs Secretary

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O Policy Ewefustion Sen J. Bennett Johnston, Const Ref . g :,/. ..- .

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,, . Ronald H. Burch ,

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- To: Date

Subject:

renelend slah at the Waterford 3 Dl8nt '

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  • ACTION SLIP f8 03) -

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I 3Cnifeb States Senate i

. July 19, 1983 -

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Respectfully referred tos .

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Nuclear Regulatory Commission i

Office of Congressional Affairs '

i Washington, D.C. 20555 -

Because of the desire of this office to be 8

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responsive to all inquiries and communications,  ! #

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your consideration of the attached is *

. requested. Your findings and views, in f  ; ,

duplicate form, along with return of the I enclosure, will be appreciat.e4 by .

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July 19, 1983 Mr. and Mrs. Ronald H. Burch 7308 Windsor Drive -

Harahan,. Louisiana 70123 .

Dear Mr. and~Mrs. Burch:

Thank you very much for letting me hear from you concerning the cracked slab at the Waterford 3 nuclear plant.

I will certainly be pleased to look into this matter for you, and have taken the liberty of contacting the appro-priate. officials here in Washington to request a report. I will be back in touch with you just as soon as I have any additional information.

I appreciate your bringing this to my attention, and send every good wish. ,,

Sincerely, J. Bennett Johnston ,

United States Senator JBJ:csb - -

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Dear Concerned Public Officer:

Would you want a nuclear power plant with a cracked slab in your neighborhood? We don't and we don't think you would either. Waterford 3 has- a cracked slabt Will the slab crack and result in a Louisiana disaster? Even as

. low probability is too high a possibility.

Once Waterford 3 is fueled, the consumer will

'.  : be. assigned the. responsibility ~for paying for Waterford 3, cracked slab and all. They .

could be paying for tiioir own destruction.

If'the crack in the slab propagains, the plant will have to be shut down. Then-the customers o,f LP&L will have to pay not only for the construction,'but also for the dismantling of Waterford 3. Why should the customer have to pay for the' mistakes of LP&L management?

- STOP WATERFORD 3 NOW, before it is fueled.

Avert the physical or financial disaster that is sure to follow. Let LP&L pay for its manage- .

ment mistakes.

Sincerely, p ,

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$ nerony or. IDENTIFICATION OF LEACHATE h

.cy, LOUISIANA POWER I, LIGHT PROJECT NUMBER 8304 cATc: September 9, 1983 nro To, Harstead Engineering Assoc Inc rummssco av Attn: Gunner Harstead copics To:

169 Kinderkamack Rd ,,

Park Ridge, NJ 07656

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RATORY No. 1-34799 . . l INTRODUCTION . , ,

s r port presents the results of our recent testing of samples you submitted for analy .

We received four s.amples; three liquid and one solid, for testing. The samples i e identified as follows: ' ' ,

1 Liquid Conduit

2. Liquid,' Pit
3. Liquid, Crack
  • Leachate 4

understand 'the seinples were taken from a reinforced concrete mat foundation. The .

indation is under hydrostatic pressure from an elevated water table. The purpose of ,

testing is to evaluate the' likelihood of. corrosion in the reinforced concrete.

CONCLUSIONS

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ed Cn the results of our testing, it is our opinion the following conclusions are iropriate: 1,  ;

1. The leachate consists primarily of calcium . carbonate and iron. Much of the -

iron is magnetic, suggesting a form such as magnetite. The iron appears as fine wire-1ike pieces under magnification.

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2. The water removed from the conduit is substantially different than the water obtained from the crack and the pit. The high pH and alkalinity of the conduit

, sample suggests the water has been in contact with the concrete for an extended period of time.

3. The chloride level in the water is sufficiently low to classify the fluid as not being aggressive.
  • TESTING METHODS AND RESULTS August 18, 1983, we received four samples for analysis. The samples consisted of ee plastic containers of liquid and one solid leachate sample. Each of the fluid iples was tested for pH using colorphast indicator sticks. Also, each fluid sample

. analyzed for chloride using the Standard Methods for Water Analysis, 407A. In addi-in, alkalinity, iron, calcium and sodium was determined for each of the fluid samples ing EPA Method 600/4-79-020. The following results were obtained:

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ij; .gpony or, IDENTIFlCATION OF LEACHATE N^,. -

DATE: September 9, 1983 BORATORY No. 1-34799 Paar: 2 i

TESTING METHODS AND RESULTS (cont.) .

Sample- Sample. Sample l

C nstituent 1 2 3 ,

pH 12.5 7.5 7.5 Iron (ppm) ND* ND 1.7 Calcium (ppm) 375 71 31

'5:dium (ppm) 2400 1400 5100 Chloride (ppm) 78 20

' Alkalinity (CACO3 ) (ppm) . 22 i 1300 - -

  • ND = Not Detected c leachate sample was analyzed using a Qarrell Ash Emission Spectrograph. The sample s placed e following in constituents carbon electrodes, and a film of the spectra was obtained with a D.C. arc.

were identified:

Concentration Constituent (s)

\ajor M Constituent Iron, Calcium -

(10% or greater) .

Minor Constituent

~

Sodium, Aluminum (10%to1%) ,

Trace Constituent Aluminum, Magnesium, (1% or less) Manganese, Titanium, Barium, Copper leachate sample was also analyzed using X-ray diffraction techniques. The diffraction

-lysis identifies crystalline material which is present in the sample. The sample tains a major amount of calcium carbonate. .

REMARKS la found on the surface of Portland cement concrete is typically compri:;ed of calcium bonate. During the hydration of Portland cement, calcium hydroxide is liberated.

the presence of -carbon dioxide, the calcium hydroxide will form calcium carbonate.

carbonation layer is generally limited to the top 1/8" of a quality concrete.

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oATz: September 9, 1983 BORATORY No. 1-34799 -

PA80 3 .-

REMARKS (cont.) .

, t ie cerrosion of reinforcing steel may form a magnetic residue such as magnetite. This irmation requires an aqueous environment where oxygen levels are low. The very low ,a

'cn ccntent of the water samples suggests the water was not in contact with steel active- 1 i c rroding. The formation of magnetite is observed frequently when steel corrodes i a chloride contaminated cementitious material and is then exposed to air. The low iltride levels found in the water suggest the pres.ence of the iron in the leachate is

>t from such a condition.

The test results are consistent with the iron originating om the surface of the slab.

l TWIN CITY TESTING AND ENGINEERING LABORATORY INC

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Chief Engineer i

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32. Conservatively asruming the existence of extensive through-cracks of the mat, assess the impact of the presence of water on the long-term structursi integrity of rebars and mat capacity. Also assess the same impacts due to other potential corrosive elements.

Response: (EBASCO) ,

The assessment has been provided in the " Applicant's Answer to Joint Intervenor's Motion to Reopen Contention," dated September 30, 1983.

Affidavit of William F. Gundsker, and in a memorandum dated August 5,1977 by A. W. Peabody /M. D. Oliveira, titled " Corrosion 'of Reinforcing Steel and Steel Containment Vessel Plates in Contact with Water," which reads in part, "...we have analysed a possible situation in the common met where supposedly groundwater seeping from concrete cracks found on the surface of the sat could corrode the reinforcing steel and the outside bottom plates of the Stewi Containment Vessel. -

It is a proven f act that concrete by its alkaline nature passivates carbon steel embedded in it.

It is also kno'nu that water in contact with concrete becomes alkaline and consequently its corrosivity to steel decreases considerably.

In addition to these factors, assuming that groundwater is left inside the crack network to a certain extent, this water will be near stagnant and without replenishment of oxygen. Consequently, the rate of corrosion under the above circumstances, if any, will be ,

negligible."

Response: (HEA) s The " existence of extensive through cracks" as hypothesized, considering the hydrostatic pressure acting at the base of the mat,'would be manifested by substantial bleeding of groundwater through such cracks. HEA reiterates

.the summary of a site inspection performed on 08/30-09/02/83. During this time'all accessible areas of the basemat were inspected and any cracks found were mapped (See HEA Report No. 8304-1, dated' 09/19/83). Subsection 4.6 of the referenced report notes that:

"The amount of moisture noted during this inspection period was minimal. In some instances dampness / moisture were present. There was, however, no evidence of seepage or migration that might have been deduced by the presence of standing water or draining along the local slope of the basemat."

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, y FE.gcdcE h ATTACEMENT 2 UNITED STATES OF AMERICA

(

NUCLEAR REGUIATORY COMMISSION ,

Before the Atomic Safety and Licensing Appeal Board ,

In the Matter of )

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Docket No. 50-382

, LOUISIANA POWER & LIGHT COMPANY )

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(Waterford Steam Electric Station, ) .

Unit 3) )

AFFIDAVIT OF WILLIAM F. GUNDAKER WILLIAM F. GUNDAKER, being first duly , sworn, deposes and says: .

1. I an employed by Ebasco Services Incorporated ("ESI")

as Director of Corrosion Engineering, and I have been involved in corrosion work for twenty-three years. A statement of my educational and professional qualifications is attached as Exhibit A. I analyzed from the corrosion viewpoint, the matters stated herein, and I make this Affidavit in support of Louisiana Power

& Light company's answer to Joint Intervanors' Motion to Reopen Contention.

2. Hairline cracking on the surface of the Waterford 3
common foundation mat has been indicated by,the presence of moisture discovered on the surface of,the mat in 1977 and in 1983. This affidavit presents my professional opinion of the potential for corrosion of the reinforcing steel within the foundation mat, and ,

the steel containment liner, as a result of the hairline cracking.

3. When steel such as the reinforcing bars ("rebars") of the Waterforkconcretematisembeddedinconcrete,theconcretewill

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b develop a film on the surface of the steel called "passivating film." This passivating film, consisting of gamma ferric oxide, ,,

j is formed by cement hydration and is maintained in the alka'line environment of the concrete. This film acts like a protective

coating applied to the rebar which precludes corrosion from taking l place on the steel robars. .

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4. For corrosion of any significance to take place on robars embedded in concrete, the protective passivation filin must first be destroyed. The primary caus,e for a breakdown of the passivation I

film is the presence of a high concentration of chlorides, as would i

be'the case in marine environments or in roadways where salts are  ;

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used for snow melting. purposes. Laboratory studies conducted by D. A. Hausmann of the American Pipe and Construction Company in

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! South Gate, California, show that the corrosion threshold for rebars is reached when the passivating film start,s breaking down.

This threshold is observed when the chloride concentration reaches i 710 ppm in the presence of free oxygen. -

5. The possible sources of chlorides contained in the water seeping through the cracks are the concrete mix water, the concrete i itself and the groundwater. Analyses of the concrete mix water taken ,

on 2/3/76 and 4/15/77 showed chloride contents of 28 ppm and 24 ppm respectively. The main sources of chlorides in the concrete are the mix water and the addition of calcium chlorides. The concrete specifications for the Waterford 3 Project states that the total ..

soluble chloride ion content in the water extracted from the concrete ,

mix should not exceed 250 ppm'and that calcium chloride shall not be e

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[ added unless specifically authorized. According to information .

obtained from ESI personnel, no calcium chlorides were added to ..

I the concrete in the Waterford 3 Project. An analysis of a '

. groundwater sample recently taken at the Waterford 3 site showed that the chloride content was 34.9 pga. Thus, it is not possible

' in my opinion for the chloride level to even approximate the 710 ppm corrosion threshold level necessary to initiate corrosion. i

6. Attempts were also recently made by ESI personnel to remove water samples from the concrete mat cracks on the floor of the

, auxiliary building for analysis. In the first attempt only about three drops of water could be extracted with a hypodermic needle.

No analysis was possible with this amount of water. During a second*

attempt which lasted several hours, approximately 10 ml of water was

{

i gathered. This amount of water allowed the U.S. Testing Laboratory i to make only a partial analysis of the sample. A comparison of some of the parameters measured in the two water samples is as follows:

Ground Water Crack Water pH 6.75 7.95 f 0.07 ppm 0.08 ppm l Iron 169 ppm 212 ppm Calcium Hardness (CACO3)

Chlorides 34.9 ppm l

67.5 ppm 85 ppm Calcium

7. The 710 ppm chloride corrosion threshold requires the t

presence of free oxygen. Bausmann's studies showed that no cor- ..

  • Sample too small for measurement.

i  ;

. . _ _ - _ _ . . . , . , _ . , - - , - . _ , , , . . , _ , . _ - . _ _ . - _ _ _ _ _ _ , , , - _ , , . _ _ . _ . -__...-.__.__.m. . . . . . . _ _ _ _ . , ~ . .

_4- ,

I, .

rosion took place in concentrations of up to 3550 ppm of chloride .

when free oxygen was not present.. While water contains dissolved oxygen, the minute amount of groundwater penetrating the cracks would in my opinion be basically classified as stagnant water, Thus, it and oxygen replenishment would be a very slow process.

is likely that the chloride corrosion threshold for the rebars in the foundation mat would be significantly higher than the 710 ppm value reported by Hausmann for corr'sion o in a, free oxygen environ-ment.

8. Another possible cause of the breakdown of the passivating Dissolved hydrogen .

film is direct chemical attack on the rebars.

  • r sulfide and dissolved carbon dioxide have been known to attack rebars in concrete. Analysis of a groundwater sample recently taken at the Waterford 3 site indicated a content of less than 0.01 ppm of hydrogens sulfide and a content of 1.32 ppm of carbon dioxide.

Both these amounts are negligible and would have no deleterious effect on the concrete mat rebars. Since the concrete is not a source for the H 8 or the CO , n direct chemical attac,k of the 2 2 robars is to be expected.

9. A common and direct indication of rust developing in con-crate rebars is the presence of a brownish stain on the surface of the concrete.' With the water penetrating through the concrete fron. .

the bottom of the mat, such a rust colored stain would tend to

  • dwposit on the top surface of the concrete mat if any measurable corrosion is taking place on the rebars. ESI personnel who have e

k inspected the cracks have reported that no such stains are evident ,.

l 1

at the Waterford 3 concrete mat .-

surface in the areas of the cracks.

In addition,-the minimal difference between the ferrous and ferric

, oxide contents on the two water samples analyzed (0.07 ppm for the groundwater and 0.08 ppm for the crack water) indicates that if any 4

l i

. corrosion of the rebar is taking place, it is negligible.

j 10. In my opinion, the amount and nature of the water in the cracks precludes Aha possibility of any significant corrosion j of the concrete mat rebars.

11. The steel liner of the containment, which is 2-1/2 feet above thu surface of the mat at its lowest point, is installed -

over fill concrete. The same protective type of passivating film

  • would develop on the surface of the liner in contact with. the con-f crate, and the same statements outlined above for the rebars can 4

be made for the liner.

i

~

12. When the cracking was discovered in 1977, my predecessor, 1

A. W. Peabody (now retired), and M. D. Oliveira (who has since left

.. ESI to return to his native land) were asked to analyze the poten-l tial for corrosion of the rebars and the outside bottom plates of the containment vessel. Their opinions were stated in memorandum COR-LW3-77-55M dated August 5,1977, a copy of which is attached as Exhibit B. On the basis of my own evaluation, I agree with the conclusions stated in their memorandum.

13. Based on my own knowledge and experience of corrosion matters, on m'y review of the literature on the subject, and on the

. . l

f:7 _ _ _

~. , ' _' , . - g-( .

data that I have .obtained related to the-Waterford 3 project, I' ,,

can state that there is no reason for me to believe that cortosion of the reinforcing steel in the concrete mat at the Waterford 3 Nuclear Plant would occur to a degree that would have any sig-

' nificance.

Nor do I have any reason to believe that the integrity of the containment liner in those areas attached to the. concrete would be affected.

'f e N.tH_ .f ' f'o s*] -

WILLIAM F. GUNDAKER t

. t

' Subscribed and sworn to before me this day of b , 1983.

/

. \

NOTARY PUBLIC k'

c ,

KATHERifft H. HMRKE My Commission Expires: NOTARY SLg5gggNewYork ComM $Nr*eEderEkis k

a 9

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