ML13085A159
| ML13085A159 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 03/26/2013 |
| From: | Kalyanam N Plant Licensing Branch IV |
| To: | |
| Kalyanam N | |
| References | |
| TAC MF0325 | |
| Download: ML13085A159 (2) | |
Text
WATERFORD STEAM ELECTRIC STATION, UNIT 3 VERBAL AUTHORIZATION OF W3-ISI-021 On December 18, 2012, The NRC staff in a telephone call with Entergy Operations Inc.
(Entergy, the licensee) provided a verbal authorization of Entergys request for alternative W3-1SI-021, ASME Code Case N-770-1 Baseline Examination Request for Alternative, for Waterford Steam Electric Station, Unit 3. The verbal authorization of the request for alternative was authorized for a period of one cycle - up until the next refueling outage (spring 2014 refueling outage).
The attendees on the call were:
Entergy NRC/NRR Chester Fugate Mike Markley Michael Haydel Tim Lupold David Viener Jay Wallace Jim Pollock Stephen Cumblidge Kaly N. Kalyanam The script used:
DE Branch Chief By letter dated November 30, 2012, Entergy Nuclear Operations, Inc., the licensee, has submitted relief request W3-1SI-021, which proposes to defer an inspection required by Title 10 of the Code of Federal Regulations Part 50 (10CFR50) Paragraph 55a(g)(6)(ii)(F) at the Waterford Steam Electric Station Unit 3 for one cycle. The licensee provided information on the impracticality associated with obtaining Appendix VIII-qualifications for the inspection procedure used to inspect the component. Therefore, the licensee requested authorization of their proposed alternative under the requirements of 10 CFR 50.55a(g)(6)(i).
The staff reviewed the licensees proposed alternative under the requirements of 10 CFR 50.55a(g)(6)(i). The Class 1 Weld 08-007, RCP-1A Cold Leg Charging Nozzle, is within the scope of ASME Code Case N-770-1 and is required to have a visual and essentially 100 percent volumetric examination, as amended by 10 CFR 50.55a(g)(6)(ii)(F)(4), prior to startup following Refueling Outage 18, which is currently in progress. Measurements taken during the outage showed that there is not a currently qualified procedure to examine Weld 08-007. The weld thickness and tapered angle are outside the tolerances for the Performance Demonstrative Initiative (PDI) mockups used for qualification. The licensee used a procedure, URS-UT-PA-DMW-1, to inspect the weld that was not qualified to Appendix VIII but was considered the best option for the weld.
As the thickness and angle measurements needed to be taken during the outage, it was not possible for the appropriate mockups to be designed and built for the procedure to be qualified prior to the outage. The NRC staff agrees delaying the plant startup until a suitable mock-up could be designed, built, and the procedure qualified would impose a severe burden on the licensee.
Weld 08-007 was inspected by this best effort examination with 100% coverage. While the inspection procedure was not Appendix VIII-qualified, the inspection procedure utilized a phased-array search unit and used a wide range and a large number of inspection angles. The wide range and large number of inspection angles make the technique robust and relatively insensitive to the taper of the weld. Additionally, the use of a phased-array search unit allows for electronic focusing, making the procedure able to compensate for thickness variations. The NRC staff has determined that the 100 percent inspection using this phased-array procedure provides reasonable assurance of public health and safety.
If the procedure URS-UT-PA-DMW-1 has its PDI qualifications expanded to cover the thickness and taper of Weld 08-007 before the next refueling outage, the inspection performed in RF18 will be considered a fully-qualified examination. Otherwise the examination will need to be repeated using an ASME Section XI, Appendix VIII-qualified procedure to inspect the weld during the next refueling outage. If an approved ASME Code Section XI procedure cannot be developed Weld 08-007 will need to be modified to achieve an inspectable configuration, and an examination performed using an ASME Code Section XI Appendix VIII qualified procedure.
In conclusion, the NRC staff finds that performing the actions needed to achieve the UT examination coverage required by 10 CFR 50.55a(g)(6)(ii)(F) would constitute a hardship. The staff also finds that there is reasonable assurance of structural integrity and leak tightness of the subject welds for a period of at least 54 months from the time of the UT examination that was performed in fall 2009.
DORL Branch Chief In conclusion, the staff has determined that granting relief for W3-1SI-021, pursuant to 10 CFR 50.55a(g)(6)(i) is authorized by law and will not endanger life or property, or the common defense and security, and is otherwise in the public interest given due consideration to the burden upon the licensee that could result if the requirements were imposed on the facility.
The staff notes that all other ASME Code,Section XI requirements for which relief was not specifically requested and approved in the subject request for relief remain applicable, including third party review by the Authorized Nuclear Inservice Inspector.