ML17265A212

Discusses Licensing Rept Appended to 970331 Lar,Revising Configuration of Certain Spent Fuel Pool Storage Racks. Recent Testing Performed on Boraflex Panels Indicates That Assumptions Are Not Conservative for Certain Region 2 Cells

ML17265A212
Person / Time
Site:	Ginna
Issue date:	03/30/1998
From:	Mecredy R ROCHESTER GAS & ELECTRIC CORP.
To:	Vissing G NRC (Affiliation Not Assigned), NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9804130037
Download: ML17265A212 (6)

Text

CATEGORY 7

REGULA Y INFORMATION DISTRIBUTIO SYSTEM (RIDS) f~

ACCESSIONS NBR:9804130037 DOC.DATE: 98/03/30 NOTARIZED: NO FACIL:50-244 Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G DOCKET 05000244 I

AUTH. NAME AUTHOR 'AFFILIATION MECREDY,R.C. Rochester Gas & Electric Corp.

RECIP'.NAME RECIPIENT AFFILIATION VISSING,G.S.

SUBJECT:

Discusses licensing rept appended to 970331 LAR,revising configuration of certain spent fuel pool storage racks. C Recent testing performed on boraflex panels indicates that assumptions are not conservative for certain Region 2 cells. A DISTRIBUTION CODE: A068D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: Responses to GL-96-04: Boraflex Degradation in Spent Fuel Storage Rac NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72). 05000244 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL 0

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PLEASE HELP US TO REDUCE WASTE. TO HAVE YOUR NAME OR ORGANIZATION REMOVED FROM DISTRIBUTION LISTS OR REDUCE THE NUMBER OF COPIES RECEIVED BY YOU OR YOUR ORGANIZATION, CONTACT THE DOCUMENT CONTROL DESK (DCD) ON EXTENSION 415-2083 TOTAL NUMBER OF COPIES REQUIRED: LTTR 11 ENCL

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O 4ND ROCHER GAS AND FLECIRIC CORPORATION ~ 89 EASI'AVENUE, ROCHESTER, N.Y. Id&f9-0001 ARFA CODE7I6 54'6-2700 ROBERT C. MECREDY Vice President March 30, 1998 Nvcteer Operations U.S. Nuclear Regulatory Commission Document Control Desk Attn: Guy S. Vissing Project Directorate I-1 Washington, D.C. 20555

SUBJECT:

Boraflex Degradation

Dear Mr. Vissing:

RG&E's License Amendment Request (LAR) dated March 31, 1997, proposed to revise the configuration of certain spent fuel pool storage racks. Appended to that LAR was a Licensing Report, which documented the technical justification for the many aspects of this proposed modification. Section 4 of that Licensing Report, titled "Criticality Evaluation", made certain assumptions regarding the distribution and composition of boraflex panels within Region 2 of the spent fuel pool. Testing recently performed on the boraflex panels indicates that these assumptions are not conservative for certain cells in Region 2. As described in LER 1998-001, "Boraflex Degradation in the Spent Fuel Pool Storage Racks Results in Plant Being in an Unanalyzed Condition" dated March 11, 1998, boraflex dissolution has occurred in certain locations, resulting in gaps larger than those assumed in the criticality evaluation. RG&E has taken prompt corrective action, removing spent fuel assemblies from the affected locations as needed to meet the criticality evaluation criteria, and maintaining a minimum boron concentration of 2,300 ppm in the spent fuel pool, monitored on a weekly basis. Interim compensatory measures will remain in place until a permanent solution to the boraflex degradation is established. Part of that permanent solution is the modification proposed in our March 31, 1997 LAR - replacement of a specified number of currently-installed spent fuel pool storage racks with racks made of borated stainless steel. We believe the current LAR should continue to be processed, and approved to allow RG&E to pursue this modification. The NRC stafFs Safety Evaluation Report (SER) approving the criticality evaluation should acknowledge that the boraflex gap sizes assumed in the criticality evaluation are not conservative, but that the interim corrective actions taken by RG&E, described above, compensate for this non-conservatism. It should also recognize that the boraflex degradation in Region 2 does not affect the new racks to be installed in Region 1. The current compensatory measures should not be considered within the license amendment process, since they are temporary conditions only. A future LAR will be submitted to the NRC for your review, detailing required Technical Specification changes that will form the basis for a final resolution of this issue (we expect this will be a combination of soluble boron credit, region 2 fuel storage restrictions, and the use of fixed neutron absorber materials, such as control rods or neutron absorber rodlets, taking no or minimal credit for boraflex panels).

9804430037 980330 PDR ADOCK 05000244 P PDR

I We anticipate these interim compensatory measures to remain in effect during the spent fuel pool rerack modification, after which a new LAR for the final resolution of this issue will be submitted.

Very truly yours, Robert C. Mecredy xc: Mr. Guy S. Vissing (Mail Stop 14B2)

Project Directorate I-1 U.S. Nuclear Regulator Commission Washington, D.C. 20555 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 U.S. NRC Ginna Senior Resident Inspector

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