ML16299A425
| ML16299A425 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 10/20/2016 |
| From: | Murray B Duke Energy Corp |
| To: | Andrew Hon Plant Licensing Branch II |
| References | |
| Download: ML16299A425 (22) | |
Text
NRR-PMDAPEm Resource From: Murray, Bill <Bill.Murray@duke-energy.com>
Sent: Thursday, October 20, 2016 1:52 PM To: Hon, Andrew
Subject:
[External_Sender] Relief Request ISI-06 Attachments: 10Apr07_NRC100038.pdf; 09May08_BSEP090043.pdf
- Andy, Per our discussion, here is the previous relief request and NRC approval for the same components covered by our latest relief request. There has been no change to the affected components or to our accessibility to those components. As we discussed, the examination is impractical and thus we have proposed an alternative (examination of only the upper welds for the proposed control rod drive housings).
Bill Murray BNP Regulatory Affairs 910.457.2842 1
Hearing Identifier: NRR_PMDA Email Number: 3122 Mail Envelope Properties (A9BEF390B5174E49A8105031DA960E3B35645F7D)
Subject:
[External_Sender] Relief Request ISI-06 Sent Date: 10/20/2016 1:52:25 PM Received Date: 10/20/2016 1:52:43 PM From: Murray, Bill Created By: Bill.Murray@duke-energy.com Recipients:
"Hon, Andrew" <Andrew.Hon@nrc.gov>
Tracking Status: None Post Office: IMADCEXCP60.nam.ent.duke-energy.com Files Size Date & Time MESSAGE 478 10/20/2016 1:52:43 PM 10Apr07_NRC100038.pdf 554559 09May08_BSEP090043.pdf 1935810 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
Recipients Received:
Acn. ML100491269 Received 4/7/10 NRC 10-0038
Acn. ML091340100
Document Control Desk BSEP 09-0043 / Page 3 cc (with enclosure):
U. S. Nuclear Regulatory Commission, Region II ATTN: Mr. Luis A. Reyes, Regional Administrator Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, GA 30303-8931 U. S. Nuclear Regulatory Commission ATTN: Mr. Philip B. O'Bryan, NRC Senior Resident Inspector 8470 River Road Southport, NC 28461-8869 U. S. Nuclear Regulatory Commission (Electronic Copy Only)
ATTN: Mrs. Farideh E. Saba (Mail Stop OWFN 8G9A) 11555 Rockville Pike Rockville, MD 20852-2738 Chair - North Carolina Utilities Commission P.O. Box 29510 Raleigh, NC 27626-0510 Mr. Jack M. Given, Jr., Bureau Chief North Carolina Department of Labor Boiler Safety Bureau 1101 Mail Service Center Raleigh, NC 27699-1101
BSEP 09-0043 Enclosure Page 1 of 8 10 CFR 50.55a Request Number RR-46 Proposed Alternative In Accordance with 10 CFR 50.55a(g)(5)(iii)
- Inservice Inspection Impracticality -
- 1. ASME Code Components Affected Code Class: 1
References:
Subarticle IWB-2500, Table IWB-2500-1 Examination Categories: B-O, "Pressure Retaining Welds in Control Rod Housings" Item Numbers: B14.10, "Welds in CRD Housing"
Description:
Volumetric Examination Coverage Component Numbers: 1C11-CRD06-11-SW1 CRD Housing Weld 1C11-CRD06-15-SW1 CRD Housing Weld 1C11-CRD10-07-SW1 CRD Housing Weld 1C11-CRD14-07-SW1 CRD Housing Weld 2C11-CRD38-47-SW1 CRD Housing Weld 2C11-CRD42-47-SW1 CRD Housing Weld 2C11-CRD46-39-SW1 CRD Housing Weld 2C11-CRD46-43-SW1 CRD Housing Weld
2. Applicable Code Edition and Addenda
The Inservice Inspection Program for the third 10-year inservice inspection interval was based on the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, 1989 Edition with no Addenda.
3. Applicable Code Requirement
Sub-article IWB-2500, Table IWB-2500-1, requires essentially 100 percent volumetric or surface examination of 10 percent of the peripheral control rod drive (CRD) housing welds (Examination Category B-O, Item No. B14.10, as defined by Figure IWB-2500-18).
Carolina Power & Light Company (CP&L), now doing business as Progress Energy Carolinas, Inc., elected to perform surface examinations on the selected CRD housing welds.
- 4. Impracticality of Compliance In accordance with 10 CFR 50.55a(g)(5)(iii), relief is requested from the requirement of the ASME Code,Section XI, Sub-article IWB-2500, Table IWB-2500-1 (Volumetric or Surface
BSEP 09-0043 Enclosure Page 2 of 8 Examination Category B-O, "Pressure Retaining Welds in Control Rod Drive Housings"),
Examination Item Number B14.10, "Welds in CRD Housing." Limited accessibility for the 36 peripheral CRD housing welds is due to the close proximity of adjacent CRD housing flanges, neutron monitoring instrumentation and associated cabling, and horizontal beams, support bars and grids.
- 5. Burden Caused by Compliance Compliance with the examination coverage requirements of the ASME Code,Section XI, would require modification, redesign, or replacement of components where geometry is inherent to the component design.
- 6. Proposed Alternative and Basis for Use Proposed Alternative In accordance with 10 CFR 50.55a(g)(5)(iii), CP&L is requesting relief for the components listed above on the basis that the required examination coverage of "essentially 100 percent" is impractical due to physical obstructions and severely limited access in the work area. As an alternative, CP&L proposes selecting the four additional upper CRD housing welds, listed below, in lieu of the four lower housing-to-flange welds. This would provide the same total number of CRD housing welds for examination (i.e., eight welds) and will be an equivalent 100 percent inspection of 10 percent of the peripheral housings.
Unit 1 Additional CRD Unit 2 Additional CRD Housing Weld Examinations Housing Weld Examinations 1C11-CRD38-47-SW2 2C11-CRD06-11-SW2 1C11-CRD42-47-SW2 2C11-CRD06-15-SW2 1C11-CRD46-39-SW2 2C11-CRD10-07-SW2 1C11-CRD46-43-SW2 2C11-CRD14-07-SW2 Basis for Use The ASME Code,Section XI, Sub-article IWB-2500, Table IWB-2500-1, requires essentially 100 percent volumetric or surface examination of 10 percent of the peripheral CRD housing welds (Examination Category B-O, Item No. B14.10, as defined by Figure IWB-2500-18).
Each CRD housing contains two pressure retraining welds. Table IWB-2500-1 requires both the upper and lower welds of each of the selected CRD housings to be examined.
BSEP 09-0043 Enclosure Page 3 of 8 BSEP has 36 peripheral CRD housings; therefore, this requires four CRD housings (i.e., a total of eight CRD housing welds) to be examined. As previously stated, each CRD housing contains two pressure retaining welds: the housing-to-flange weld and the housing tube-to-tube weld. The housing-to-flange weld is located in the inaccessible lower section of the CRD housing, whereas the housing tube-to-housing tube weld is located in the accessible upper section of the CRD housing (i.e., shown on Drawings 0-FP-05609; C-24004, Sheet 26-1; and C-02404, Sheet 26-1; provided in Attachments 1, 2, and 3, respectively).
Limited access for the 36 peripheral CRD housing-to-flange weld welds is due to the work area under the reactor vessel being highly congested, as shown in the photographs in . Physical obstructions imposed by design, geometry, and materials of construction include vessel appurtenances, insulation support rings, structural and component supports, adjacent CRD housing flanges, and neutron monitoring instrumentation and associated cabling. These obstructions are not practical to remove or replace to achieve 100 percent volumetric or surface coverage of the welds in the CRD housings. The upper housing welds are without obstruction and can be completely examined.
Therefore, as an alternative, CP&L proposes selecting four additional upper CRD housing welds in lieu of the four lower housing-to-flange welds. This would provide the same total number of CRD housing welds for examination (i.e., eight welds).
CP&L performed qualified surface examinations that achieved the maximum, practical amount of coverage obtainable within the limitations imposed by the design of the components. The examinations conducted confirmed satisfactory results, with no unacceptable flaws being identified and no evidence of degradation mechanisms.
Percent of Code-Required Volume Achieved Original Sample Additional Sample 1C11-CRD06-11-SW2 100% Coverage Achieved 1C11-CRD38-47-SW2 100% Coverage Achieved 1C11-CRD06-15-SW2 100% Coverage Achieved 1C11-CRD42-47-SW2 100% Coverage Achieved 1C11-CRD10-07-SW2 100% Coverage Achieved 1C11-CRD46-39-SW2 100% Coverage Achieved 1C11-CRD14-07-SW2 100% Coverage Achieved 1C11-CRD46-43-SW2 100% Coverage Achieved 2C11-CRD38-47-SW2 100% Coverage Achieved 2C11-CRD06-11-SW2 100% Coverage Achieved 2C11-CRD42-47-SW2 100% Coverage Achieved 2C11-CRD06-15-SW2 100% Coverage Achieved 2C11-CRD46-39-SW2 100% Coverage Achieved 2C11-CRD10-07-SW2 100% Coverage Achieved 2C11-CRD46-43-SW2 100% Coverage Achieved 2C11-CRD14-07-SW2 100% Coverage Achieved As Class 1 Examination Category B-O components, a visual (VT-2) examination is also performed on these components during system pressure tests each refueling outage. This was completed during the Unit 1 2008 refueling outage (i.e., the B117R1 outage) and Unit 2 2009 refueling outage (i.e., the B219R1 outage), and no evidence of leakage was identified for these components. Reactor coolant system leak rate limitations and atmospheric particulate radioactivity monitoring also ensure that any leakage would be detected prior to gross failure.
BSEP 09-0043 Enclosure Page 4 of 8
- 7. Duration of the Proposed Alternative Use of the proposed alternative is applicable to the third 10-year inservice inspection interval at BSEP, Units 1 and 2. The third 10-year interval began on May 11, 1998, and ended on May 10, 2008, for Unit 1 and will end on May 10, 2009, for Unit 2.
- 8. Precedents Similar relief request was granted for the Pilgrim Nuclear Power Station, as listed in Reference 1.
- 9. References
- 1. Letter from U.S. Nuclear Regulatory Commission (USNRC) to Entergy Nuclear Operations, Inc., Third 10-Year Interval Inservice Inspection Program Plan Request for Relief Request No. PRR-42, Revision 1 - Pilgrim Nuclear Power Station (TAC No. MD6767), dated June 27, 2008, ADAMS Accession Number ML081300415.
BSEP 09-0043 Enclosure Page 5 of 8 ATTACHMENT 1
BSEP 09-0043 Enclosure Page 6 of 8 ATTACHMENT 2
BSEP 09-0043 Enclosure Page 7 of 8 ATTACHMENT 3
BSEP 09-0043 Enclosure Page 8 of 8 ATTACHMENT 4 Figure 1 - Under-Vessel Area Figure 2 - Under-Vessel Area, Looking Upwards