ML063050534

Relief Request 06-ON-004 Request for Additional Information Seeking NRC Approval to Use Alternatives to ASME Code Section XI ISI Requirements for the Plants

ML063050534
Person / Time
Site:	Oconee
Issue date:	10/26/2006
From:	Brandi Hamilton Duke Energy Corp
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
06-ON-004, TAC MD2887
Download: ML063050534 (4)

Text

BRUCE H HAMILTON Vice President oEnergy. Oconee Nuclear Station Duke Energy Corporation ONO] VP / 7800 Rochester Highway Seneca, SC 29672 864 885 3487 864 885 4208 fax bhhamilton@duke-energy.com October 26, 2006 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

SUBJECT:

Duke Power Company LLC d/b/a Duke Energy Carolinas, LLC (Duke)

Oconee Nuclear Station, Unit 1 Docket Number 50-269 Relief Request 06-ON-004 Request for Additional Information On August 24, 2006 Duke submitted Relief Request 06-ON-004 pursuant to 10 CFR 50.55a(a)(3)(i), requesting NRC approval to use alternatives to the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI inservice inspection (ISI) requirements for the Oconee Nuclear Station, Unit 1, 2, & 3. This proposed alternative approach is to support application of full structural weld overlays on various pressurizer nozzle-to-safe end welds and will provide an acceptable level of quality and safety.

By letters dated September 11, 2006 and October 5, 2006, Duke responded to e-mail requests from the NRC Staff for additional information regarding several issues contained within the relief request.

On October 18, 2006, Duke received another request by telephone for clarification on the additional information provided in the October 5, 2006 letter.

Upon review, the author of the submittal recognized that a portion of the intended wording had been inadvertently omitted from the Oconee response for question 2. Enclosed is a corrected response to question 2.

www. duke-energy. corn

Nuclear Regulatory Commission October 26, 2006 Page 2 If you have any questions or require additional information, please contact Randy Todd at (864)-885-3418.

Sincerely, Bruce H. Hamilton Site Vice President Oconee Nuclear Station Enclosure Cc:

W. D. Travers, Region II Administrator U.S. Nuclear Regulatory Commission Sam Nunn Atlanta Federal Center, 23 T85 61 Forsyth St., SW Atlanta, GA 30303-8931 L. N. Olshan., Senior Project Manager (ONS)

U. S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 8 G9A Rockville, MD 20852-2738 D. W. Rich NRC Senior Resident Inspector Oconee Nuclear Station

ENCLOSURE OCONEE NUCLEAR STATION Corrected Response To Second Request for Additional Information Request for Relief No. 06-ON-004 Pressurizer Alloy 600 Weld Overlays (TAC No. MD2887)

NRC Question 2:

Provide a commitment to submit within 14 days from completion of UT examination of the weld overlays, a report that summarizes the results of the examinations, consistent with the September 14, 2006 letter from Exelon to NRC regarding Byron Station, Unit 1 Relief Request 13R-03.

Response

Acceptance of ultrasonic indications in weld overlay repairs using Section XI acceptance criteria has been approved by NRC in past weld overlay applications (e.g. References 1, 2). The following information will be submitted to the NRC within fourteen days of completion of the final UT on each unit included in this relief request. Also included in the results will be a discussion of any repairs to the overlay material and/or base metal and the reason for the repair.

" a listing of flaw indications detected1

" the disposition of all indications using the standards of ASME Section Xl, IWB-3514-2 and/or IWB-3514-3 criteria and, if possible,

• the type and nature of the indications2 1 The recording criteria of the ultrasonic examination procedure to be used for the examination of the Oconee pressurizer overlays (SI-UT-1 26 Rev.0) requires that all suspected flaw indications, regardless of amplitude, be investigated to the extent necessary to provide accurate characterization, identity, and location. Additionally, the procedure requires that all indications, regardless of amplitude, that cannot be clearly attributed to the geometry of the overlay configuration be considered flaw indications. SI-UT-1 26, Rev. 0, is our supplier's procedure for phased array ultrasonic inspection of weld overlays. This procedure is based on the EPRI procedure for manual conventional ultrasonic inspection of weld overlays (PDI-UT-8) and has the same requirements for procedure and personnel qualification.

2 The ultrasonic examination procedure states that all suspected flaw indications should be plotted on a cross sectional drawing of the weld and that the plots should accurately identify the specific origin of the reflector.

Request for Relief No. 06-ON-004 Corrected Response To Second Request for Additional Information Page 2 References (1) Safety Evaluation by the Office of Nuclear Reactor Regulation related to Three Mile Island Nuclear Station, Unit 1 (TMI-1) Request for Relief from Flaw Removal, Heat Treatment and Non-Destructive Examination (NDE) Requirements for the Third 10-Year Inservice Inspection (ISI)

Interval, Amergen Energy Company, LLC Docket No. 50-289, July 21, 2004.

(2) Safety Evaluation by the Office of Nuclear Reactor Regulation Inservice Inspection Program Relief Request ISIR-17, Donald C. Cook Nuclear Plant, Unit 1 (DCCNP-1), Indiana Michigan Power, Docket No. 50-315, February 10, 2006.