ML20141H847

Discusses Open Item Associated W/Section 6.1 of AP600 Ser. Subj Section Requires Westinghouse Action to Close

ML20141H847
Person / Time
Site:	05200003
Issue date:	07/30/1997
From:	Slosson M NRC (Affiliation Not Assigned)
To:	Liparulo N WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
References
NUDOCS 9708010225
Download: ML20141H847 (4)

Text

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l pntcu yw  % UNITED STATES g j

't NUCLEAR REGULATORY COMMISSION l

WASHINGTOR 0.C. 2056M001  !

• • • • • ,o July 30, 1997 gr #O  !

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Mr. Nicholas J. Liparulo, Manager Nuclear Safety and Regulatory Analysis Nuclear and Advanced Technology Division i

Westinghouse Electric Corporation l P.O. Box 355 )

Pittsburgh, PA 15230 l

SUBJECT:

OPEN ITEM ASSOCIATED WITH SECTION 6.1 0F THE AP600 SAFETY EVALUATION REPORT (SER) J l

Dear Mr. Liparulo:

l The staff has completed its review d the Materials and Chemical Engineering aspects of the AP600 Standard Safety Analysis Report (SSAR), Section 6.1.2, 1 Organic Materials. The input to the SER for this section has an open item that requires Westinghouse's action to close.

The open item is basically an extension of DSER Open Item 6.1.2-1 and is l related to the use of protective coatings used on containment. It is the i staff's judgment that the AP600 containment coating on the outside surface is an essential feature for the heat transfer function of the passive containment cooling system. In addition, the staff believes that the coatings on surfaces inside containment must retain integrity so as not to interfere with the recirculation of condensed steam or water following a design basis accident. l Consequently, the staff has concluded that the containment coatings on both I the interior and outside surface of containment perform significant safety  !

functions.

Westinghouse regards the containment coatings for the AP600 as being non-safety related. The staff has the following concerns about classifying the AP600 containment coatings as non-safety related: )

1) The staff is concerned that any improperly applied coatings within containment may peel off and thus prevent other safety-related '

] systems or components from performing their functions. Containment coatings at operating plants have been observed to peel off over large areas. On the basis of ex)eriences with operating reactors, concerns have been raised over tie potential for unqualified coat-t ings, or incorrectly applied qualified coatings, in conjunction with other loss-of-coolant accident generated debris, to cause blockage of the sump screens. For the purpose of the certified design, ,f Westinghouse is relying on the COL applicant to demonstrate that the N1 V interior containment coatings will not interfere with the passive )

core cooling system through a coating transport evaluation. The staff disagrees with the Westinghouse conclusion. The staff's position is that assurance of the integrity of the containment coating needs to be established prior to the design certification i()

phase.

9708010225 970730

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3 i a r j Mr. Nicholas J. Liparulo July 30,1997 t

! 2) The inorganic zinc coating on the containment shell exterior and interior regions above the operating deck provides the basis for the performance of the passive containment cooling system (PCS). The

! inorganic zinc coating selected for the AP600 was used in the  ;

i Westinghouse flat plate test, the water distribution test and the i

! large scale test facilities. Surface wettablity on the exterior of ,

l~ the containment dome and vertical shell, in the form of expected j

surface area coverage based on the applied flow rate, and the ex- i pected behavior of the water film are based on the attributes of the  !

inorganic zinc coating as evaluated in these test facilities. These characterizations form the basis for the design basis licensing ,

!. analyses. In addition, the characteristics of the inorganic zinc j coating on the interior of the containment dor and shell support

the PCS performance based on the large scale test data. It is the i staff's conclusion that the inorganic zinc coating is an integral

aspect of the PCS design. j Westinghouse states in the AP600 SSAR that the containment coatings are j maintained to provide. corrosion protection for the containment pressure ]i i boundary and for other carbon steel components within containment. In addition, concrete surfaces inside containment are coated to 3rotect them from chemical attack and enhance decontaminability. Westinghouse las concluded that failure of the containment coatings will not prevent functioning of the engineered safety features and has classified the coatings as non-safety related.

The staff does not yet have a sufficient basis to agree with Westinghouse's non-safety related classification of the containment coatings for the reasons stated above. Westinghoun thould either provide additional justification for its position by addressing ne staff's concerns or reclassify the coatings used inside and on the exta. Ior of containment as safety.related. Open Item 6.1.2-1 remains open.

The Open Item Tracking System number 969 associated with this DSER open item identifies the Nuclear Regulatory Commission status column as " Action N." The staff requests that this status be changed to " Action W" until Westinghouse acceptably addresses the staff's concerns on this issue.

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Mr. Nicholas J. Liparulo -3_ July 30,1997 If you have any questions regarding this matter, you can contact Bill Huffman I at (301) 415-1141.

l Sincerely, 1

Seymour H. Weiss for i

Marylee M. Slosson, Acting Director ,

Division of Reactor Program Management I Office of Nuclear Reactor Regulation I Docket No.52-003 cc: See next page i

DISTRIBUTION- I Docket File PDST R/F MSlosson PUBLIC SWeiss TQuay  ;

TQuay TKenyon BHuffman l JSebrosky DJackson GHolahan, 0-8 E2 ACRS (11) JMoore, 0-15 B18 WDean, 0-5 E23 CBerlinger, 0-8 H7 GHolahan, 0-8 E2 JKudrick, 0-8 H7 l BSheron, 0-7 D26 GBagchi, 0-7 HIS JStrosnider, 0-7 D4 GGeorgiev, 0-7 HIS MSnodderly, 0-8 H7 EThrom, 0-8 H7 RElliott, 0-8 H7 RLobel, 0-8 H7 JDavis, 0-7 04 ,

DOCUMENT NAME: A: ISSUE-6.1-2 To seceive e copy of this document,Indcote in the boa: "C* = Copy without attachment / losure "E" = Copy with attachment / enclosure

• N*

• No copy 0FFICE PM:PDST:DRPM BCpE@S:DE D:dE Why BC:SCSB:DSSA NAME WCHuffman:s @ @-GfagcKi BSherbr/ CBerlinge6 h6 DATE 0745/97 37/74/97 07/15/97 07/pr/97 0FIICE D:DSSL s FM D:PDST:DRPM (A)D:DRPM r JL,,

NAME GHolfi Lan ; P TRQuay oto MMSlosson X W DATE 07AS '97 M 07/d/97 07/30/97 htf) 0FFICIAL RECOR) COPY

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.Mr. Nicholas J. Liparulo Docket No.52-003 Westinghouse Electric Corporation AP600 e

cc: Mr. B. A. McIntyre Mr. Ronald Simard, Director  !

Advanced Plant Safety & Licensing Advanced Reactor Programs Westinghouse Electric Corporation Nuclear Energy Institute Energy Systems Business Unit 1776 Eye Street, N.W.  ;

P.O. Box 355- Suite 300 Pittsburgh, PA 15230 Washington, DC 20006-3706 '

Mr. Cindy L. Haag Ms. Lynn Connor Advanced Plant Safety & Licensing Doc-Search Associates Westinghouse Electric Corporation Post Office Box 34 Energy Systems Business Unit Cabin John, MD 20818 Box 355 Pittsburgh, PA 15230 Mr. James E. Quinn, Projects Manager l

. LMR and SBWR Programs Mr. S. M. Modro GE Nuclear Energy Nuclear Systems Analysis Technologies 175 Curtner Avenue, M/C 165 l Lockheed Idaho Technologies Company San Jose, CA 95125  :

Post Office Box 1625 Idaho Falls, ID 83415 Mr. Robert H. Buchholz ,

GE Nuclear Energy ,

Mr. Sterling Franks 175 Curtner Avenue, MC-781 i U.S. Department of Energy San Jose, CA 95125 NE-50 19901 Germantown Road Barton Z. Cowan, Esq. '

Germantown, MD 20874 Eckert Seamans Cherin & Mellott 600 Grant Street 42nd Floor  :

Mr. Frank A. Ross Pittsburgh, PA 15219 '

U.S. Department of Energy, NE-42  :

Office of LWR Safety and Technology Mr. Ed Rodwell, Manager ,

19901 Germantown Road PWR Design Certification r

~ Germantown, MD 20874 Electric Power Research Institute l 3412 Hillview Avenue .!

Mr. Charles Thompson, Nuclear Engineer Palo Alto, CA 94303 j AP600 Certification i

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NE-50 19901 Germantown Road l Germantown, MD 20874 i i

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