RS-17-159, Supplemental Information for Dresden Nuclear Power Station Fifth Inservice Inspection Interval Relief Request 15R-16
| ML17319A334 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 11/15/2017 |
| From: | Simpson P Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| EPID: L-2017-LLR-0136, RS-17-159 | |
| Download: ML17319A334 (2) | |
Text
- ANMW 4300 Winfield Road Warrenville, IL 60555 ExeLon Generation(-) 630 657 2000 Office RS-17-159 10 CFR 50.55a(z)(1)
November 15, 2017 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Dresden Nuclear Power Station, Units 2 and 3 Renewed Facility Operating License Nos. DPR-19 and DPR-25 NRC Docket Nos. 50-237 and 50-249
Subject:
Supplemental Information for Dresden Nuclear Power Station Fifth Inservice Inspection Interval Relief Request 15R-16
References:
- 1. Letter from P. R. Simpson (Exelon Generation Company, LLC (EGC)) to NRC, "Dresden Nuclear Power Station Fifth Inservice Inspection Interval Relief Request 15R-16," dated November 7, 2017 (Accession No. ML17132A293)
- 2. NRC Memorandum, "Summary of Teleconference on November 9, 2017, Regarding Verbal Authorization of Relief Request to Use Alternative for Dresden Nuclear Power Station, Units 2 and 3 (EPID: L-2017-LLR-0136),"
dated November 13, 2017 (Accession No. ML17317A900)
In Reference 1, EGC requested NRC approval of a relief request in accordance with 10 CFR 50.55a(z)(1) for Dresden Nuclear Power Station (DNPS), Units 2 and 3. Specifically, EGC requested approval to use alternatives as implemented by the Performance Demonstration Initiative (PDI) Program in lieu of the requirements within American Society of Mechanical Engineer (ASME)Section XI, 2007 Edition 2008 Addenda, Appendix VIII, Supplement 11, "Qualification Requirements for Full Structural Overlaid Wrought Austenitic Piping Welds."
Implementing the PDI Program allows EGC to perform preservice inspections of an emergent weld overlay repair required by the identification of recordable ultrasonic (UT) indications in Weld JP1A/N20A-6 (i.e., a reducer-to-pipe weld on the Unit 2 "A" jet pump instrumentation loop header) during the current DNPS, Unit 2 refuel outage.
During the teleconference summarized in Reference 2, the NRC granted verbal authorization of EGC's Reference 1 request; however, during the teleconference, EGC informed the NRC that subsequent to the submittal of Reference 1, EGC determined that the repair methodology described in Reference 1 is no longer reflective of the weld repair plan. Specifically, the repair methodology discussed in Reference 1, Attachment 1, Section 4, "Reason for Request," (i.e.,
ASME Section XI Code Case N-504-4, "Alternative Rules for Repair of Classes 1, 2, and 3 Austenitic Stainless Steel Piping Section XI, Division 1 ") is not the methodology that will be used
November 15, 2017 U.S. Nuclear Regulatory Commission Page 2 for the weld repair. This is due to the fact that Code Case N-504-4 is incorporated into Nonmandatory Appendix Q, "Weld Overlay Repair of Classes 1, 2, and 3 Austenitic Stainless Steel Weldments," of the 2007 Edition of ASME Section XI. Since the Code of record for the DNPS, Units 2 and 3 fifth 10-year Inservice Inspection Program interval is the 2007 Edition with 2008 Addenda, EGC will be performing the repairs to Weld JP1A/N20A-6 in accordance with ASME Section XI, Nonmandatory Appendix Q, not ASME Code Case N-504-4.
The purpose of this letter is to provide a formal written update regarding the repair methodology that is being used to effect repairs to the DNPS, Unit 2 Weld JP1A/N20A-6 as discussed during the November 9, 2017, teleconference.
There are no regulatory commitments contained within this letter.
Should you have any questions concerning this letter, please contact Mr. Mitchel A. Mathews at (630) 657-2819.
Si cerely, Patrick R. Simpson Manager Licensing Exelon Generation Company, LLC