BSEP 17-0104, Proposed Alternative in Accordance with 10 CFR 50.55a(z)(1) for Reactor Pressure Vessel Nozzle-to-Vessel Weld Examination
| ML17334A109 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 11/29/2017 |
| From: | Wooten B Duke Energy Progress |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| BSEP 17-0104 | |
| Download: ML17334A109 (6) | |
Text
Brunswick Nuclear Plant P.O. Box 10429 Southport, NC 28461 November 29, 2018 Serial: BSEP 17-0104 10 CFR 50.55a(z)(1)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Subject:
Brunswick Steam Electric Plant, Unit No. 2 Renewed Facility Operating License No. DPR-62 Docket No. 50-324 Proposed Alternative In Accordance With 10 CFR 50.55a(z)(1) for Reactor Pressure Vessel Nozzle-to-Vessel Weld Examination
Reference:
Letter from Douglas A. Broaddus (USNRC) to Michael J. Annacone (Carolina Power & Light Company), Request for Alternatives to the Reactor Pressure Vessel Nozzle-to-Vessel Weld and Inner Radius Examinations (TAC Nos.
ME3854 and ME3855), dated January 31, 2011, ADAMS Accession Number ML110060504.
Ladies and Gentlemen:
In accordance with 10 CFR 50.55a(z)(1), Duke Energy Progress, LLC (Duke Energy), hereby requests approval of an alternative to the requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),Section XI, 2001 Edition through 2003 Addenda for the Brunswick Steam Electric Plant (BSEP), Unit No. 2.
Examination of 100 percent of the reactor pressure vessel (RPV) nozzle-to-vessel shell welds is required in the ASME Code,Section XI, Subarticle IWB-2500, Table IWB-2500-1, Category B-D, Full Penetration Welded Nozzles - Inspection Program B, Item B3.90, Nozzle-to-Vessel Welds.
Duke Energy received approval (i.e., Reference) of Inservice Inspection Program Alternative ISI-05 to examine a minimum of 25 percent of the nozzle-to-vessel welds, including at least one nozzle from each system and nominal pipe size with the exception of the recirculation outlet nozzles, in accordance with ASME Code Case N-702, Alternative Requirements for Boiling Water Reactor (BWR) Nozzle Inner Radius and Nozzle-to-Shell WeldsSection XI, Division 1.
Duke Energy requests approval of the enclosed alternative ISI-08, to the requirement of IWA-2430(d), to allow the examination of Unit 2 nozzle-to-vessel weld 2B11-RPV-N11B to be completed during the Unit 2 refueling outage scheduled for March 2019 (i.e., B2R24). Approval of this proposed alternative is requested on the basis that it provides an acceptable level of quality and safety. The proposed inservice inspection alternative ISI-08 is provided as an enclosure of this letter.
U.S. Nuclear Regulatory Commission Page 2 of 2 Please refer any questions regarding this submittal to Mr. Lee Grzeck, Manager - Regulatory Affairs, at (910) 832-2487.
Sincerely,
- ?. j/~
Bryan 8. Wooten Director - Organizational Effectiveness Brunswick Steam Electric Plant WRM/wrm
Enclosure:
10 CFR 50.55a Request Number ISl-08 cc (with enclosure):
U.S. Nuclear Regulatory Commission, Region II ATTN: Ms. Catherine Haney, Regional Administrator 245 Peachtree Center Ave, NE, Suite 1200 Atlanta, GA 30303-1257 U.S. Nuclear Regulatory Commission ATTN: Mr. Gale Smith, NRC Senior Resident Inspector 84 70 River Road Southport, NC 28461-8869 U.S. Nuclear Regulatory Commission ATTN: Mr. Andrew Hon (Mail Stop OWFN 8G9A) (Electronic Copy Only) 11555 Rockville Pike Rockville, MD 20852-2738 Andrew.Hon@nrc.gov Chair - North Carolina Utilities Commission (Electronic Copy Only) 4325 Mail Service Center Raleigh, NC 27699-4300 swatson@ncuc.net Mr. Cliff Dautrich, Bureau Chief North Carolina Department of Labor Boiler Safety Bureau 1101 Mail Service Center Raleigh, NC 27699-1101
BSEP 17-0104 Enclosure Page 1 of 4 10 CFR 50.55a Request Number ISI-08 Proposed Alternative In Accordance with 10 CFR 50.55a(z)(1) 2B11-RPV-N11B Nozzle-to-Vessel Weld Examination
- 1. ASME Code Components Affected Unit(s) Affected:
Brunswick Steam Electric Plant (BSEP), Unit 2 Code Class:
ASME Code,Section XI, Class 1
References:
Subarticle IWB-2500, Table IWB-2500-1 Examination Categories:
B-D, "Full Penetration Welded Nozzles - Inspection Program B" Item Numbers:
B3.90, Nozzle-to-Vessel Weld Component Numbers:
==
Description:==
Volumetric Examination
- 2. Applicable Code Edition The Inservice Inspection Program for the fourth 10-year inservice inspection interval is based on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, 2001 Edition with 2003 Addenda. The fourth 10-year inservice inspection interval began on May 11, 2008, and is currently scheduled to end on May 10, 2018.
3. Applicable Code Requirement
ASME Code,Section XI, 2001 Edition through the 2003 Addenda, Table IWB-2500-1, Examination Category B-D, Item B3.90, requires a volumetric examination of all nozzle-to-vessel welds each interval.
Approved Inservice Inspection Program Alternative ISI-05 (i.e., Reference 7.1) requires a volumetric examination of a minimum of 25 percent of the nozzle-to-vessel welds, including at least one nozzle from each system and nominal pipe size, in accordance with ASME Code Case N-702.
ASME Code Section XI, Subarticle IWA-2430(d), requires the following:
(d) For components inspected under Program B, the following shall apply:
(1) Each inspection interval may be reduced or extended by as much as one year.
Adjustments shall not cause successive intervals to be altered by more than one year from the original pattern of intervals. If an inspection interval is extended, neither the start and end dates nor the inservice inspection program for the successive interval need be revised.
BSEP 17-0104 Enclosure Page 2 of 4 An alternative to the requirement of IWA-2430(d) is requested to allow the examination of Unit 2 nozzle-to-vessel weld 2B11-RPV-N11B to be completed during Unit 2 refueling outage scheduled for March 2019 (i.e., B2R24).
4. Reason for Request
Volumetric examination of the 2B11-RPV-N11B nozzle-to-vessel weld is required during the fourth 10-year Inservice Inspection Interval to satisfy the requirement of Inservice Inspection Program Alternative ISI-05. Although an examination of this weld was performed in March 2009 during the first refueling outage (i.e., B2R19) of the fourth 10-year inservice inspection interval, this examination cannot be credited for this inspection interval because it was performed to satisfy requirements for the third 10-year inservice inspection interval.
The alternative proposed in this request is being submitted to allow an examination of this weld to be performed during refueling outage B2R24 in 2019 so the examination may be credited towards satisfying the requirements for the fourth 10-year inservice inspection interval.
5. Proposed Alternative and Basis for Use
Proposed Alternative In accordance with 10 CFR 50.55a(z)(1), an alternative is requested to the requirement of IWA-2430(d)(1) that Each inspection interval may be reduced or extended by as much as one year.
In lieu of the requirement of IWA-2430(d)(1) above, the proposed alternative is to extend the Unit 2 fourth 10-year inservice inspection interval to no later than the end of refueling outage B2R24 (i.e., currently scheduled for March 2019) solely to perform volumetric examination for reactor pressure vessel instrumentation nozzle-to-vessel weld 2B11-RPV-N11B.
Approval of the proposed alternative is requested prior to the end of the fourth 10-year inservice inspection interval, which is currently scheduled to end on May 10, 2018.
Basis for Use The fourth 10-year inservice inspection interval began on May 11, 2008, and is currently scheduled to end on May 10, 2018.
The fourth inservice inspection interval for Unit 2 has already been extended such that the original pattern of intervals has been altered by approximately one year. As such, the current Unit 2 inservice inspection interval cannot be extended per IWA-2430(d)(1) to allow the examination of nozzle-to-vessel weld 2B11-RPV-N11B to be performed during refueling outage B2R24.
By Reference 7.1, Duke Energy received approval of Inservice Inspection Program Alternative ISI-05 to examine a minimum of 25 percent of the nozzle-to-vessel welds, including at least one nozzle from each system and nominal pipe size with the exception of
BSEP 17-0104 Enclosure Page 3 of 4 the recirculation outlet nozzles, in accordance with ASME Code Case N-702, Alternative Requirements for Boiling Water Reactor (BWR) Nozzle Inner Radius and Nozzle-to-Shell WeldsSection XI, Division 1.
To comply with the ASME Code,Section XI, and the NRC-approved Alternative ISI-05, a minimum of two of the six instrumentation nozzle group nozzles (i.e., N11A, N11B, N12A, N12B, N16A, and N16B) are required to be examined during the fourth 10-year inservice inspection interval.
As stated in Section 4 above, the examination of nozzle-to-vessel weld 2B11-RPV-N11B during refueling outage B2R19 cannot be credited for satisfying the requirements of the fourth 10-year inservice inspection interval.
For the fourth 10-year inservice inspection interval, nozzle-to-vessel weld 2B11-RPV-N11B had been scheduled for examination during refueling outage B2R23. During reviews to confirm the inspection scope for refueling outage B2R23, the examination of this weld was removed from the outage scope because the examination completed during refueling outage B2R19 was mistakenly credited towards satisfying the examination requirement for the fourth inservice inspection interval. There are no Unit 2 plant outages remaining in the fourth 10-year inservice inspection interval during which this examination can performed.
Nozzle N11B inner radius (i.e., component 2B11-RPV-N11B-IRS) was examined during refueling outage B2R20 and this examination was credited to the fourth 10-year inservice inspection interval.
As stated above, the nozzle-to-vessel weld 2B11-RPV-N11B was examined in refueling outage B2R19 (i.e., the first outage of the fourth 10-year inservice inspection interval) in March 2009. A manual conventional ultrasonic examination was conducted in accordance with ASME Code,Section XI, Appendix VIII requirements. 94.6 percent total coverage of the 2B11-RPV-N11B nozzle-to-vessel weld volume was obtained, comprised of 89.2 percent axial coverage and 100 percent circumferential coverage. Axial examination was partially obstructed by the adjacent recirculation nozzle N4C outside diameter radius taper. No recordable indications were noted during the examination of the 2B11-RPV-N11B nozzle-to-vessel weld. Furthermore, no recordable indications were detected during examination of the 2B11-RPV-N12B nozzle-to-vessel weld that was examined in accordance with Alternative ISI-05 during the fourth 10-year inservice inspection interval.
Because the previous examination of the nozzle-to-vessel weld 2B11-RPV-N11B was performed in March 2009, the proposed alternative to examine this weld during refueling outage B2R24 in March 2019 provides an acceptable level of quality and safety as it maintains an approximate 10-year interval between successive examinations. The examination of nozzle-to-vessel weld 2B11-RPV-N11B in refueling outage B2R24 will not be credited towards satisfying the examination requirements for the fifth 10-year inservice inspection interval.
- 6. Duration of the Proposed Alternative This proposed alternative is requested until the end of refueling outage B2R24, currently scheduled for March 2019.
BSEP 17-0104 Enclosure Page 4 of 4
- 7. References 7.1.
Letter from Douglas A. Broaddus (USNRC) to Michael J. Annacone (Carolina Power & Light Company), Request for Alternatives to the Reactor Pressure Vessel Nozzle-to-Vessel Weld and Inner Radius Examinations (TAC Nos. ME3854 and ME3855), dated January 31, 2011, ADAMS Accession Number ML110060504.