ML20002B296

Forwards Safety Evaluation by Ofc of Nuclear Reactor Regulation Supporting Authorization to Chemically Decontaminate Primary Coolant Sys at Facility

ML20002B296
Person / Time
Site:	Dresden
Issue date:	12/09/1975
From:	Goller K Office of Nuclear Reactor Regulation
To:	Bolger R COMMONWEALTH EDISON CO.
References
FOIA-80-548, FOIA-80-550 NUDOCS 8012110276
Download: ML20002B296 (1)

Text

__

UNITED STATES

~

NUCLEAR REGULATORY COMMISSION b

W ASHINGToN. D. c. 20555 l

1

-s :1 December 9, 1975 1(;;;mm u

w.

Docket No. 50-10 E

Commonwealth Edison Company ATIX: Mr. R. L. Bolger Assistant Vice President

)

Post Office Box 767 Chicago, Illinois 60690 Gentlemen:

The NRC staff has co=pleted its review of your requests dated December 1$,

1974, April 1,1975, and April ik 1975, for authorization to carry out A chemical decontamination of the interior surfaces of 'the Dresden 1 Prinary Coolant System. Based on our review of the decontamination program, we have concluded that the program can be conducted with reasonable assurance that the health, and safety.of the public will not be endangered.

During our review three items were identified as unresolved.

It is our

{

understanding that they will be resolved as follows:

g 1.

• Ihe testing program will be completed and the results submitted for k

the re, view and approval of the NRC staff prior to performing the I

L

~~

proposed i:Nemical cleaning.

r 2.

A pre-service inspection program for the primary coo.lant boundary will be formulated and submitted for our review and approval prior to returning the reacter to service.

3.

A post-cleaning surveillance program which includes additional j-surveillance specimens and a specimen withdrawal and examination schedule will be submitted for our review and approval prior to i'

returning the reactor to service.

On this basis the Commonwealth Edison Company is authorized to initiate its proposed chemical decontamination of Dresden Station Unit 1.

~

The staff's review is summarized in the attached Safety Evaluation.

Sincerely, Karl R. Goller, Assistant Director

(

for Operating Reactors

\\

Division of Reactor Licensing

.s I-5

Enclosure:

Safety Evaluation 8 012 3 3 g f

..yyg

~ 6 g ;rW

?=K UNITE 3 STATES r-w.

} ~]

NUCl. EAR REGULATORY COMMISSION

~

W ASHINoToN. D. C. 2055s i.j-({

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION U

SUPPORTING AUTHCRIZATION TO CHEMICALLY DECONTAMINATE THE PRIMARY COOLING SYSTEM AT DRESDEN UNIT 1 Com0NWEALTH EDISON COMPANY DRESDEN NUCLEAR POWER STATION UNIT 1 DOCKET NO. 50-10 t

IhTRODUCTION By letters dated December 16,1974, April 1,1975 and April 14, 1975, the Commonwealth Edison Company (CECO) requested authorization to carry

[

out a chemical decontamination of the interior surfaces of the Dresden f~

Unit 1 primary coolant system.

n

.7 The purpose of the decontanination is to remove a deposition of activated

(

corrosion products which is tightly bonded to the primary coolant system W

piping and components. The presence of the corrosion products in the M

WE-system results in high levels of radiation in adjacent areas and limits Et TjE access to these areas for the purpose of in-service inspection, routine maintenance and plant modifications.

Ceco has tentatively scheduled the chemical cleaning project to begin E

in January 1977 with an anticipated return to service scheduled for July 1977.

EVALUATION

~

y::

The staff's review of CECO's proposed chemical decontanination of the interior surfaces of the Dresde'n Unit 1 primary coolant system has been completed. The. results of this review are as follows:

1.

Environmental Impact Ir p

The chenical decontamination of the Dresden 1 primary coolant system i..:.:

will be performed entirely within a closed decontamination system.

Q The system has been designed so that no chemical or radiological h

wastes will be released to the environment from the decontamination process. All wastes generated in the process will be either solidified h

for offsite burial at a licensed burial ground or reproceued for reuse onsite. The solid wastes produced are similar in type and quantity to.

g those handled routinely at the site. Therefore, no adverse environmental

\\

impacts are anticipated due to the decontamination.

F ii:

'N.'.

',yOI 19'

j jk

=i Y::

2 p

'X f

E 5=

2.

Mater.ials Compatibility G

h.:

ne staff Las reviewed the results of the material testing program

}4 that has been carried out in support of the proposed Dresden 1 F

decontamination program. The test program was organized to look at corrosive effects during the decontamination process and possible p

residual effects during subsequent reactor operation.

Fw Based upon our review of the results of the testing program completed

=

to date, we have concluded that the test program adequately evaluated Ei those aspects of the materials compatibility that we consider to be P

important. As a result of our discussions with CECO's consultant, Dr. Craig Cheng of Argonne National Laboratory, we find that the g.

remaining program will be conducted in a manner that will answer our 7

presently unresolved concerns and the test results will be adequately interpreted and reported.

HE We conclude that upon the successful completion of the testing program

{i described in the submittals and with an adequate surveillance and inspection program, the Dresden Nuclear Power Station Unit I can be subjected to the described chemical cleaning process without' undue corrosion or other deleterious materials compatibility effects that

(

would adversely effect the integrity of the primary coolant system M

s.:.

gg._.

and connected systems.

g

%~==

• 2 A mall number of items of concern have not been resolved to the n..

staff's full satisfaction at this time. However, we conclude that M

authorization to carry out the chemical decontamination should be im granted in anticipation of the successful resolution'of these open

=..

items in the near future. H e following open items are identified

[_E at this time as requiring resolution to the staff's satisfaction:

7.e (a) The materials test program will be completed and the test

,.?

results will be analyzed and reviewed prior to the beginning

1. f of the cleaning process.

(b) Surveillance specimens 15 addition to those now planned wil2 be determined by mutual agreement with the applicant and a schedule E

for specimen withdrawal will be stated.

(c) A pre-service inspection program for the primary coolant boundary

=y and safety related systems will be formulated and performed prior to return to power.

9=

l w

li 1

n,,

3

.c J r

-, _. 7..

$hbh' 3.

Effluent Treatment Systems We have determined that the effluent treatment system, if constructed as described in the CECO submittals, is capable of handling the types and quantities of effluents expected to be generated by the decon-tamination program. Our review was limited to the use of the system for chemical decontamination only, and use of the system for any other purpose subsequent to that program must be reviewed prior to such use.

4.

Radiological Safeqr I

We have further concluded that the radiological safety program described in the submittals is adequate to assure that the health and safety of the public and the onsite personnel will not be endangered by the Dresden 1 decontaniaation project.

CONCLUSION We have concluded, based on the considerations discussed above, that:

(1) because the chemical cleaning does not involve a significant increase in the probability or consequences of accidents previously considered and i

{-

does not involve a significant decrease in a safety margin, the cleaning i.

jgg.

project does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not jj qq;;p be endangered by operation in the proposed manner, and (3) such activities j

will be conducted in co=pliance with the Co= mission's regulations and the F

issuance of this mnendment will not be inimical to the common defense and r

security or to the health and safety of the public.

Date:

December 9, 1975 e

r x.

~,

_ _, - - ~

,m.-

r

• n

[.<'[?, j. 'd.'.. ! \\"

~

h V

i 2 s cn 1:.

r..

m:

n Gecket sia. 50-10 p.=;:.

!.h U

il

0. L. Ziecunn, Cnief 1;.-

Operating Reactors 3 ranch ;2 i:

RE'/IE'A 0F ORESDE;l 1 CHEMICAL CLEEGiG LICE;iSI; G S '5.IITTAl.

5 G

The chemical cleaning licensing submittal for Dresder: I has been reviewed. The dec.:ntamination prograc as proposed raleases no i

effluents to the enviren;aent ana :na solid wastes produced are similar in type and quantity to tnose handled routinely at tne E.

Dresden site. Therefore, no adverse environ:cental 1:r;icts due E

to decontamination are anticipatad.

[.i...

R h.

Original signed by B.J. Er.i._c

[=.h..

.id.I

~1,';....

'~

3. J. Youngolood, Cnief

E+

Environuen:al Projects 3ranen 3 m.

Division of Reac'wr Licensing DISTRIBUTIO:1 OccKet Fila h

EP-3 Reading IE i!RR Reading B. J. Youngblood, EP-3 S. S. Kirslis, EP-3 /

- f.5..

=

P. '.i. O'Cennor, OR /

g.:,.:

2 p+

5#5i.

r--

c f/14

.e."

n u

RL h_ N "T. ~ + :<

! w un,Repc-)rc...

...) :E?-3.

! SS.irsiis:ws

@g-3J eptybicoc l 3/25/75

. 6./ b, 7.5 3 f.4. 7. 3....

l

.p...

1... 9 a.dC4.7.<a

~J u. s. sev === = s av **'at* = a o'* c ri * *. e s..s e.

To I o 2 t o 3 2.3

._