ML20238E384

Comments on Draft NRC Info Notice on Boraflex.Suggestions for Improving Clarity & Accuracy of Notice to Reflect Author & Northeast Technology Corp Views Discussed

ML20238E384
Person / Time
Site:	Quad Cities
Issue date:	07/30/1987
From:	Lambert R ELECTRIC POWER RESEARCH INSTITUTE
To:	Hodge C Office of Nuclear Reactor Regulation
Shared Package
ML20238E264	List: ML20238E262 ML20238E291 ML20238E322 ML20238E348 ML20238E384 ML20238E387
References
NUDOCS 8709140309
Download: ML20238E384 (2)

Text

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,i Electric Power Research institute L

L July 30, 1987-

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Mr. C. Vernon Hodge.

Division of' Operational Events Assessment l

Office of Nuclear Reactor Regulation

'U.S.

NRC Washington,'DC 20555

Dear Mr. Hodge:

Thank you for the' opportunity to review the draft notice on i

Boraflex.

Given the large amount of information to consider, I believe you have, in general, done a good job of 4

getting the facts distilled down into a good summary.

The

.following comments are suggestions for improving the clarity or accuracy of the notice and reflect both my views and those of our contractor, Northeast Technology Corp.

Page 1, 12 The early use of the term " degradation" without aome explanation could be misleading and not l

really consistent with the title of the notice.

A j

suggested wording is "... gaps that have been found in l

irradiated Boraflex (...).

Also, there is some sample l

coupon data that suggests that other radiation / chemical degradation phenomena may occur that could be a factor 1

in determining the maximum service life of Boraflex."

i Page 1, 12 The phrase "to preclude a similar problem" may be troublesome as it may be interpreted as requiring rack replacement.

I suggest using the phrase "that i

address such problems should they be found to be..."

Page 1, last 1 Replace the words " cell walls" with "Boraflex panels."

l Page 2, 13 The last sentence makes it sound as though the l

degree of panel and coupon degradation were similar, which is not true.

The only similarity was the j

occurrence of the whitish discoloration found in both.

A better wording may be "... minimal degradation, a slight discoloration on the Boraflex surface near the edge of the sheet, of the panel exposed..."

j l

8709140309 870710 R

PDR-ADOCK 05000254

S PDR RWL:vgs/3771MS71

' 3412 HilMew Avenue, Post office Box 10412, Palo Alto, CA 94303 Telephone (415) 855 2000 g

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.Mr..C. Vernon Hodge July 30, 1987 page 2 l

4 Page 2, last 1 The currentLEPRI program is not collecting

.other. gap data from utilities, but is only correlating coupon data'.

On theLlast?line the word " understanding" is suggested to replace " picture."

Page 3, 12; A redraft suggestion for this paragraph:is as follows:

Because of the scarcity of data, the initial EPRI model has assumed that volume changes are isotropic.

Should

.this prove not:to be the case, the projected maximum l

gap size may be in error.

It is also noteworthy that the new shrinkage data being ge'.erated by BISCO appear to confirm that the model pred.ctions-for shrinkage-were, as expected, very conservative.

Page 3, 13 Suggested rewording of the first sentence is as follows:

i In polymer materials such as Borafisx, the primary l

radiation damage mechanisms are crosslinking and l

scissioning.

Page 3, 14 In line 3 the word " determine" should be replaced with the words " consider and evaluate."

If the above comments are unclear or if you would like to further discuss them, please give me a call.

Also, if ma]or rewrites are made of the draft notice, I would be pleased to give it a last-look review.

)

L Thanks for the opportunity to comment and I hope our

-suggestions are constructive and of some help to you.

Sincerely, h

p $0lO<

v/

6 Ray-@. Lambert-1 LTechnical Specialist

' Nuclear Systems & Materials attachment I

cc:

R. F. Williams - EPRI l

' Ken Lindquist - Northeast Technology Corp.

RWL:vgs/3771MS71

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