ML043410074

Supporting Information Regarding Amendment Application Nos. 224 and 208, Proposed Change Number (PCN) 554, Technical Specification (TS) 6.5.2.15, Containment Leakage Rate Testing Program

ML043410074
Person / Time
Site:	San Onofre
Issue date:	12/02/2004
From:	Scherer A Southern California Edison Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
IN-92-020
Download: ML043410074 (5)

Text

SOUTHERN CALIFORNIA A. Edward Scherer EDISON & Manager of Nuclear Regulatory Affairs An EDISON INTERN.ATIONALS Company December 2, 2004 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555

Subject:

Docket Nos. 50-361 and 50-362 Supporting information regarding Amendment Application Nos. 224 and 208, Proposed Change Number (PCN) 554, Technical Specification (TS) 6.5.2.15, Containment Leakage Rate Testing Program, San Onofre Nuclear Generating Station Units 2 and 3

Dear Sir or Madam:

By letter from D. E. Nunn (SCE) to the Document Control Desk (NRC) dated June 30, 2004, Southern California Edison (SCE) submitted Amendment Application Nos. 224 and 208.

Per NRC Staff request, SCE is submitting the enclosed San Onofre Nuclear Generating Station (SONGS) Independent Safety Engineering Group Operating Experience Evaluation, Subject, "NRC Information Notice 92-20, Inadequate Local Leak Rate Testing," dated June 22, 1992. This document is listed as Reference 9 in the June 30, 2004, SONGS ILRT Extension Application. Please note that procedure number changes have occurred at SONGS since 1992, and the local leak rate test (LLRT) procedures are now SO23-3-3.51.1 through S023-3-3.51.9.

P.O. Box 128 San Clemente. CA 92674-0128 949-368-7501 Fax 949-368-7575 dVa

Document Control Desk December 2, 2004 If you have any questions or require additional information, please contact Mr. Jack Rainsberry at (949) 368-7420.

Sincerely, Enclosure cc: B. S. Mallett, Regional Administrator, NRC Region IV B. M. Pham, NRC Project Manager, San Onofre Units 2 and 3 C. C. Osterholtz, NRC Senior Resident Inspector, San Onofre Units 2 and 3

i O EVALIUATION Or

~ N C -i~?aR JUNE 22, 1992 DISTRIBUTION

SUBJECT:

INFORMATION ONLY: NRC Information Notice 92-20, "Inadequate Local Leak Rate Testing" Attached is an information Only" copy of the subject ISEG operating experience evaluation. Should you have any questions or need further information, please call me.

Attachment

INDEPENDENT SAFETY ENGINEERING GROUP OPERATING EXPERIENCE EVALUATION JUNE 8, 1992 DOC NO:.-r. IN 92-20.

PRIORITY:'

INADEQUATE LOCAL LEAK RATE TESTING

¢-;BACKRObND - 'Tif On February 25, 1991, the tommonwealth Edison Company performed a Type B LLRT on the containment penetration bellows for penetration X-25 at Quad Cities, Unit 1, and found an acceptable measured leakage rate of 6 standard cubic feet per hour. The LLRT was performed by pressurizing the volume between the two plies of the bellows through a test connection. On February 28, while performing the primary containment Integrated.leak rate test, they found excessive leakage from the penetration. An Investigation of the incident revealed cracks In the bellows that were not found by the LLRT. The two piles of the bellows wqre found to be in contact, restricting the flow of the test medium to the crack locations.

Incidents at Dresden, Unit 2 and Perry, Unit I leaks were found In flanged fittings that had not been properly leak tested during ILRTs. The Dresden incident Involved a torus purge exhaust Inner Isolation valve whose Inner flange was not challenged during the ILRT The Perry Incident was with the inboard flange of a seal leakoff line on a relief valve that was not challenged during the ILRT An Incident at Clinton, Unit 1 Involved lines that were considered to be water sealed but, In actuality terminated above the suppression pool minimum drawdown level.

EVALUATION San Onofre, Units 2 and 3 have double metallic expansion bellows penetrations on the refueling canal. The Commonwealth Edison problem was caused by the close proximity of the Inner and outer bellows and the low Included volume. This is not a concern at San Onofre, Units 2 and 3. The refueling canal penetration bellows has a minimum spacing between the inner and outer bellows of over 6 Inches and an Included volume of approximately 17 cubic feet which will preclude a similar occurrence.

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IN 92-20 JUNE 8, 1992 San Onofre, Unit-1 has an expansion bellows on the Main Steam System, which also has a large gap between plies and has a minimum Included volume of 14.1 cubic feet In the smaller chamber.

Both ISEG and Station Technical Engineering have reviewed the LLRT procedures (

S023-V.13.2 through S023-V-3.13.51) for the possibility of leakage paths such as flanges that are not properly accounted for In testing. No leakage paths were found.

The Clinton event Is specific to boiling water reactors and Is not applicable to San Onofre.

CONCLUSION The events described In this Information Notice have been reviewed by Station Technical Engineering and ISEG and, no similar problems at san Onofre have been found. No further action Is required.

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