ET 06-0048, Additional Information Related to the Relaxation Request from the First Revised NRC Order EA-03-009 Regarding Requirements for Nondestructive Examination of Nozzles Below the J-Groove

Additional Information Related to the Relaxation Request from the First Revised NRC Order EA-03-009 Regarding Requirements for Nondestructive Examination of Nozzles Below the J-Groove

ML063110631
Person / Time
Site:	Wolf Creek
Issue date:	11/01/2006
From:	Garrett T Wolf Creek
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
EA-03-009, ET 06-0048
Download: ML063110631 (4)

Text

WF CREEK NUCLEAR OPERATING CORPORATION Terry J. Garrett November 1, 2006 Vice President, Engineering ET 06-0048 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

Reference:

Letter ET 06-0035, dated October 5, 2006, from T. J. Garrett, WCNOC to USNRC

Subject:

Docket No. 50-482: Additional Information Related to the Relaxation Request from the First Revised NRC Order EA-03-009 Regarding Requirements for Nondestructive Examination of Nozzles Below the J-Groove Gentlemen:

The Reference submitted, as a contingency, a relaxation request from the February 20, 2004 First Revised Order EA-03-009 which required nondestructive examination of the reactor pressure vessel head penetration nozzle base material and J-groove weld that attaches the nozzle base material to the underside of the head. The Reference requested relaxation from the requirements for nondestructive examination of the five penetration nozzles (penetration nozzles 74 through 78) for which Wolf Creek Nuclear Operating Corporation (WCNOC) may not be able to obtain coverage as specified in the Order and proposed that the lower boundary of the ultrasonic inspection extend to the maximum extent possible but not less than 0.30 inches from the toe of the J-groove weld on the downhill side. In the current refueling outage, nondestructive examinations were performed and the required coverage for penetration nozzles 77 and 78 could not be obtained. However, the examination coverage exceeded that proposed for the lower boundary of the ultrasonic inspection.

Section 5 of the relaxation request proposes the duration of the relaxation of this request. In a teleconference on October 25, 2006, between Nuclear Regulatory Commission (NRC) and WCNOC personnel, it was identified that this section had not addressed the potential for a revised analysis in which the crack-growth acceptance criteria are exceeded. Attachment I provides a revised Section 5 which supercedes Section 5 of the Reference. Attachment II provides a List of Regulatory Commitments that supercedes the Regulatory Commitments in Attachment II of the Reference.

P.O. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 k1IO/

An Equal Opportunity Employer M/F/HCNET

ET 06-0048 Page 2 If you have any questions concerning this matter, please contact me at (620) 364-4084, or Mr.

Kevin Moles at (620) 364-4126.

Very truly Terry J. Garrett TJG/rlt Attachments cc: J. N. Donohew (NRC), w/a B. S. Mallett (NRC), w/a G. B. Miller (NRC), w/a Senior Resident Inspector (NRC), w/a

Attachment I to ET 06-0048 Page 1 of 1 Additional Information Related to the Relaxation Request from the First Revised NRC Order EA-03-009 Wolf Creek Nuclear Operating Corporation (WCNOC) letter ET 06-0035, dated October 5, 2006, submitted, as a contingency, a relaxation request from the February 20, 2004 First Revised Order EA-03-009 which required nondestructive examination of the reactor pressure vessel head penetration nozzle base material and J-groove weld that attaches the nozzle base material to the underside of the head. Section 5 of the relaxation request proposes the duration of the relaxation of this request. In a teleconference on October 25, 2006, between Nuclear Regulatory Commission (NRC) and WCNOC personnel, it was identified that this section had not addressed the potential for a revised analysis in which the crack-growth acceptance criteria are exceeded during the subsequent operating cycle. Provided below is a revised Section 5.

5. Duration of Relaxation WCNOC requests relaxation of this requirement for end of cycle fifteen refueling outage inspection and all future inspections where ultrasonic examination techniques are used to inspect the five affected RPV head penetration nozzles in Response to the requirements of the First Revised NRC Order EA-03-009, or until inspection technology is developed to a state where the examination volume can be extended to full compliance with the Order, or information is received from the NRC regarding non-acceptance of the crack growth formula in MRP-55.

The crack-growth rate formula in the structural integrity evaluation for WCNOC is the same as reported in industry report MRP-55. If the NRC Staff finds that the crack growth formula in industry report MRP-55 is unacceptable, WCNOC will revise its analysis that justifies relaxation of the order within thirty days after NRC informs WCNOC of an NRC approved crack-growth rate formula. If WCNOC's revised analysis shows that the crack growth acceptance criteria are exceeded prior to the end of the current operating cycle, this relaxation request will be rescinded and WCNOC will, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, submit to the NRC written justification for continued operation. If the revised analysis shows that the crack-growth acceptance criteria are exceeded during the subsequent operating cycle, WCNOC will, within 30 days, submit the revised analysis for NRC review. If the revised analysis shows that the crack-growth acceptance criteria are not exceeded during either the current or the subsequent operating cycle, WCNOC will, within 30 days, submit a letter to the NRC confirming that its analysis has been revised.

Attachment IIto ET 06-0048 Page 1 of 1 LIST OF REGULATORY COMMITMENTS The following table identifies those actions committed to by WCNOC in this document. This List of Regulatory Commitments supercedes the regulatory commitments in Attachment II of letter ET 06-0035 dated October 5, 2006. Any other statements in this submittal are provided for information purposes and are not considered to be commitments. Please direct questions regarding these commitments to Mr. Kevin Moles at (620) 364-4126.

COMMITMENT Due Date/Event If the NRC Staff finds that the crack growth formula in industry Within 30 days of report MRP-55 is unacceptable, WCNOC will revise its notification of an analysis that justifies relaxation of the order within thirty days NRC approved after NRC informs WCNOC of an NRC approved crack-growth formula.

rate formula.

If WCNOC's revised analysis shows that the crack growth Within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of acceptance criteria are exceeded prior to the end of the discovery that current operating cycle, this relaxation request will be acceptance criteria rescinded and WCNOC will, within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, submit to the will be exceeded.

NRC written justification for continued operation.

If the revised analysis shows that the crack-growth acceptance Within 30 days of criteria are exceeded during the subsequent operating cycle, analysis revision WCNOC will, within 30 days, submit the revised analysis for NRC review. If the revised analysis shows that the crack-growth acceptance criteria are not exceeded during either the current or the subsequent operating cycle, WCNOC will, within 30 days, submit a letter to the NRC confirming that its analysis has been revised.