ML20081B858

Responds to NRC Comments & Recommendations Re Realignment of Simplified BWR Design Certification Review

ML20081B858
Person / Time
Site:	05200004
Issue date:	02/27/1995
From:	Quinn J GENERAL ELECTRIC CO.
To:	Borchardt R Office of Nuclear Reactor Regulation
References
MFN-009-95, MFN-9-95, NUDOCS 9503170011
Download: ML20081B858 (3)

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'. GENuclearEnergy  ;

.larnes E. Quinn, Projects Manager GeneralElectric LMR and SBWR Programs 175 Curtner Avenvek165 San . lose, CA 951251014 '

408 925-1005 (phone) 408 925-3991(facsimile)

February 27,1995 MFN No. 009-95 _;

Docket STN 52-004 >

i Document Control Desk t U. S. Nuclear Regulatory Commission Washington DC 20555 Attention: Richard W. Borchardt, Ilirector Standardization Project Directorate P

Subject:

Realignment of the Simplified Boiling Reactor (SBWR)

Design Certification Review.

References:

1. Letter, R. W. Borchardt, (NRC) to Patrick W. Marriott, Same Subject, dated November 28,1994.

2. GE Report Number NEDO-32391, Revision A, SBWR Test and Analysis Program Description (TAPD), dated September,1994. e 1

This letter prosides the GE response to the NRC comments and recommendations provided in the Reference 1 letter. We were delayed in preparation of this response while we restructured the FY95 work to accommodate the resolution of the DSER and ACRS comments on the TAPD (Ref. 2) within the limited FY95 resources. The munbering scheme corresponds to that used in the referenced letter.

1. Probabilistic Risk Assessment (PRA) i While we acknowledge the desirability of actively pursuing PRA activities concurrently with the testing phase, we have decided not to do this (at least not untiljuly '95) for '

the reasons below.

a. The program realignment effectively put the PRA on hold until the SSAR/ Design Review effort is resumed;

b. The present SBWR PRA is substantially complete and adequate for the present Testing /TRACG phase of the program. We acknowledge that the SBWR PRA must be updated to reflect the final design, however, we do not expect that this ,

update will identify new sequences or success paths that would warrant further investigation through testing; l

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c. The SBWR design is very mature and has been substantially inflm. a by PRA activities. The most recent PRA was the third conducted for the SBWR. Several resultant design improvements are documented in Subsection 19.2.3 of the S%R.

2. Radiation Protection

a. We agree the Staff and GE need to meet to identify and resolve issues related to fission-product transport and release model qualification for design basis accident analysis. Ilowever, we do not see any potential significant impact on the Test and Analysis Program or qualification of TRACG. The areas in which we believe that the Staff will desire further discussion are already under consideration on the AP-600 licensing docket, with the possible exception of safety envelope mixing elliciency and we would expect to have that discussion after the SSAR/ Design Review is resumed.

h. GE met with Dr. Jay Lee of the NRC on November 16,1994, in Switzerland and discussed AIDA. The UCB analysis will be discussed, as needed, after the SSAR/ Design Review is resumed.

3. Performance and Quality Evaluation We support the current dialogue regarding the quality assurance programs at the various testing facilities. The Applicant's reliability assurance program will be further described in future PRA revisions, following SSAR/ Design Rcview resumption. GE will continue all QA activities necessary to support SBWR Testing and TRACG.

We appreciate receiving the summary of the staff's Requests for Additional Information (RAls).

As indicated in the Summary of Requests for AdditionalInformation the NRC has issued 1092 RAls against the SBWR. As descnbed in Section 1.2 of the TAPD (Ref. 2),

the SBWR is an evolutionary design which traces its commercial demonstration and operating history back before 1960. Most features of the SBWR have been taken directly from licensed commercial BWRs with long operating histories. The SBWR has drawn together the best of previously licensed plant features to establish a simpler passive plant. As such we would expect that a commensurately smallincrement of new review would be required with all the years of successful licensing review and

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. 1 MFN No. 009-95 Page 3 operating history. We would expect that most of the questions should have already been asked on the SBWR. Perhaps there are process improvements that could be identified to improve the SBWR SSAR/ Design Review efficiency. ,

If further discussion of these matters is necessary, please contact Mr. John Leathe'rman at (408) 925-2023.

Sincerely, f

9 Jan e nn, Projects Manager .- ;

V LMR and SBWR Programs l

cc: P. A. Boehnert (NRC/ACRS)

I. Catton (ACRS)

S. Q. Ninh (NRC)

J. H. Wilson (NRC)

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