NRC 2012-0089, Supplement to 10 CFR 50.55a Request. Relief Request 1 -RR-4 Re-Examination of the Unit 1 Reactor Pressure Vessel Lndication on the a Lnlet Nozzle Weld Fifth Ten-Year Lnservice Lnspection Program Interval

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Supplement to 10 CFR 50.55a Request. Relief Request 1 -RR-4 Re-Examination of the Unit 1 Reactor Pressure Vessel Lndication on the a Lnlet Nozzle Weld Fifth Ten-Year Lnservice Lnspection Program Interval
ML12349A364
Person / Time
Site: Point Beach NextEra Energy icon.png
Issue date: 12/14/2012
From: Meyer L
Point Beach
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
NRC 2012-0089
Download: ML12349A364 (5)


Text

NEXT ENEHC+\

/- POINT BEACH December 14,201 2 NRC 2012-0089 10 CFR 50.55a U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Point Beach Nuclear Plant Unit 1 Docket 50-266 Renewed License No. DPR-24 Supplement to 10 CFR 50.55a Request. Relief Request 1-RR-4 Re-Examination of the Unit 1 Reactor Pressure Vessel lndication on the "A" lnlet Nozzle Weld Fifth Ten-Year lnservice lnspection Proqram Interval

References:

(1) NextEra Energy Point Beach, LLC letter to NRC, dated November 9,2012, 10 CFR 50.55a Request, Relief Request 1-RR-4 Re-Examination of the Unit 1 Reactor Pressure Vessel lndication on the "A" lnlet Nozzle Weld Fifth Ten-Year lnservice lnspection Program Interval (MLI 2318A125)

(2) NRC e-mail to NextEra Energy Point Beach, LLC, dated November 23,2012, Point Beach Nuclear Plant, Unit 1 - Acceptance Review re: Relief Request 1-RR-4 (TAC No. ME9905)

In Reference (I), NextEra Energy Point Beach, LLC (NextEra) requested that the Nuclear Regulatory Commission (NRC) grant relief from the requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (B&PV Code),Section XI, 2007 Edition with Addenda through 2008 for the re-examination of the Point Beach Nuclear Plant (PBNP) Unit 1 reactor pressure vessel (RPV) "A" lnlet Nozzle Weld RC-32-MRCL-Alll-03.

Relief was requested on the basis that alternative methods would provide an acceptable level of quality and safety.

In Reference (2), the NRC informed NextEra that supplemental information is required in order for the NRC staff to make an independent assessment regarding acceptability of the proposed relief request.

This submittal provides the supplemental information. Specifically, additional information was added in the Section 'Proposed Alternative and Basis for Use', an additional precedent was added and NextEra added the two Regulatory Commitments listed in this cover letter. This submittal replaces Reference (1) in its entirety.

NextEra requests approval of this request prior to March 15, 2013. The Unit 1 RPV examinations will be conducted during the Spring 2013 refueling outage. The requested duration of this relief request is until the end of the First Period of the Fifth lnspection Interval, which would end July 31, 2015.

NextEra Energy Point Beach, LLC, 6610 Nuclear Road, Two Rivers, WI 54241

Document Control Desk Page 2 Summaw of Renulatow Commitments This supplement contains the following Regulatory Commitments:

Flaw(s) detected and measured as less than 50% through-wall in depth shall be adjusted by adding the industry-proposed correction factor of the RMS error -

0.125 inches to the depth of the flaw; and For flaw(s) detected and measured as 50% through-wall depth or greater, and to remain in service without mitigation or repair, NextEra shall submit flaw evaluations to the NRC for review and approval prior to reactor startup.

If you have questions or require additional information, please contact Mr. Michael Millen, Licensing Manager, at 9201755-7845.

In accordance with the provisions of 10 CFR 50.91, a copy of this submittal has been provided to the designated Wisconsin Official.

Very truly yours, NextEra Energy Point Beach, LLC Enclosure cc: Regional Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC PSCW Mr. Mike Verhagan, Department of Commerce, State of Wisconsin

ENCLOSURE RELIEF REQUEST 1-RR-4 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT UNIT 1 Request for Relief in Accordance with 10 CFR 50.55a(a)(3)(i)

Alternative Requirements to ASME Section XI Appendix VII (Supplements 2 and 10)

Examinations of Class 1 Pressure Retaining Welds Conducted from the Inside Surface ASME Code Component(s) Affected Code Class: 1 Examination Category: Category R-A ltem Number: R1.20 Component Number: RC-32-MRCL-A111-03 Component Designation: Elbow to Inlet Nozzle at 328.5" Drawing Number: ISI-1120

Applicable Code Edition and Addenda

NextEra Energy Point Beach, LLC (NextEra) is currently in the Fifth Ten-Year inservice inspection (ISI) interval. The current IS1 program is based on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code,Section XI, 2007 Edition with Addenda through 2008. Testing of personnel, procedures, and equipment for the ultrasonic examination of applicable Class 1 and 2 components is governed by Appendix VIII, "Performance Demonstrationfor Ultrasonic Examination Systems," of the ASME Code,Section XI.

Applicable Code Requirements The examination of Class 1 and 2 piping welds are required to be performed using procedures, personnel and equipment qualified to the criteria of the ASME B&PV Code,Section XI, Appendix VIII, and specifically Supplement 10, "Qualification Requirements for Dissimilar Metal Piping Welds," for the examination of ltem R1.20 nozzle-to-piping dissimilar metal welds.

Supplement 10, Paragraph 3.3, "Depth-Sizing Test," Subparagraph (c) states, "Examination procedures, equipment, and personnel are qualified for depth-sizing when the RMS [root mean square] error of the flaw depth measurements, as compared to the true flaw depths, do not exceed 0.125 in. (3 mm)."

Reason for the Request NextEra is performing a volumetric re-examination of the RC-32-MRCL-Alll-03dissimilar metal (DM) weld from the inside diameter (ID) surface during the upcoming refueling outage as required by Paragraph IWB-2420(b).

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NextEra proposes using an alternative RMS error depth-sizing requirement as compared to the 0.125-inch RMS error value stated in Appendix VIII, Supplement 10. A NextEra representative confirmed with the Performance Demonstration Initiative (PDI) Administrator on September 25, 2012, that no vendor has successfully demonstrated compliance with the Code-required 0.125-inch RMS value for qualification tests for examinations conducted from the ID surface (for either stand-alone Supplement 10 or combined Supplement 2 and 10 qualifications).

Proposed Alternative and Basis for Use Pursuant to 10 CFR 50.55a(a)(3)(i), relief is requested for an alternative requirement that will provide an acceptable level of quality and safety.

NextEra has verified through the PDI Administrator that the examination vendor selected to perform the scheduled re-examinations at Point Beach Nuclear Plant (PBNP) has achieved a 0.212-inch RMS error for the Supplement 10 qualification, a 0.21 1-inch RMS error for the Supplement 2 qualification, and a 0.21 1-inch RMS error for the Combined Supplement 2 and10.

For the re-examination of indications recorded on weld RC-32-MRCL-Alll-03 (Supplement 1O),

NextEra proposes to apply the difference between the examination vendor's achieved RMS error and the Supplement 10 required 0.125-inch RMS error to actual flaw depths during depth-sizing of indications.

Applying the difference between the required RMS error and the achieved RMS error to the actual flaw being sized will ensure a conservative bounding flaw depth for the applicable dissimilar metal weld to be examined at PBNP Unit 1.

If the previously reported non-ID connected flaws are determined to be connected to the piping ID surface, NextEra will supply the flaw evaluations performed, along with the measured size as determined by ultrasonic testing (UT), for review. The examination vendor will use eddy current testing in order to determine if the flaw is ID surface breaking. If an additional flaw is detected and depth sizing is required, the inner profile of the weld, pipe and nozzle in the region of and surrounding the flaw will be provided along with an estimate of the percentage of potential surface areas with UT probe lift-off. The flaw degradation mechanism will be determined with aid from the initial and additional nondestructive examination data collected.

Flaw(s) detected and measured as less than 50% through-wall in depth shall be adjusted by adding the industry-proposed correction factor of the RMS error - 0.125 inches to the depth of the flaw. For flaw(s) detected and measured as 50% through-wall depth or greater, and to remain in service without mitigation or repair, NextEra shall submit flaw evaluations to the NRC for review and approval prior to reactor startup.

Duration of Proposed Alternative The requested duration of this relief request is until the end of the First Period of the Fifth Inspection Interval, which would end July 31, 2015.

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Precedents A similar relief request was granted to PBNP and McGuire Nuclear Station:

NRC letter to FPL Energy Point Beach LLC, Point Beach Nuclear Plant, Units 1 and 2 -The Fourth 10-Year Interval lnservice Inspection Program Plan Requests for Relief No. RR-21 (TAC Nos. MD 8319 and MD8320), dated August 25,2008 (ML081690887)

NRC letter to McGuire Nuclear Station, Duke Energy Carolinas, LLC - McGuire Nuclear Station, Unit 2 - Proposed Relief Request 12-MN-003(TAC No. ME8712), dated September 24,201 2 (MLI2258A363)

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