Correspondence Related to NRC Regulations in 10 CFR 50.55a(g)(6)(ii)(E) and 10 CFR 50.55a(g)(6)(ii)(F)

By Federal Register Notice 73 FR 52730 dated September 10, 2008, NRC issued final rule requiring augmented inservice inspections for reactor coolant system piping and vessel nozzle butt welds fabricated with Alloy 82/182/600 materials at pressurized water reactors (PWRs) in accordance with ASME Code Case N-722 "Additional Examinations for PWR Pressure Retaining Welds in Class 1 Components Fabricated with Alloy 600/82/182 Materials Section XI, Division 1," with conditions specified in paragraphs (g)(6)(ii)(E)(2) through (4) of Section 50.55a, Title 10 of the Code of Federal Regulations.

By Federal Register Notice 76 FR 36232 dated June 21, 2011, NRC issued final rule and amended the regulations to require implementation of ASME Code Case N-722-1 "Additional Examinations for PWR Pressure Retaining Welds in Class 1 Components Fabricated with Alloy 600/82/182 Materials Section XI, Division 1," with conditions specified in paragraphs (g)(6)(ii)(E)(2) through (4) of Section 50.55a, Title 10 of the Code of Federal Regulations.

By Federal Register Notice 76 FR 36232 dated June 21, 2011, NRC issued final rule requiring augmented inservice inspections for reactor coolant system piping and vessel nozzle butt welds fabricated with Alloy 82/182/600 materials at pressurized water reactors (PWRs) in accordance with ASME Code Case N-770-1 "Alternative Examination Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds Fabricated With UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities Section XI, Division 1," with conditions specified in paragraphs (g)(6)(ii)(F)(2) through (10) of Section 50.55a, Title 10 of the Code of Federal Regulations, by the first refueling outage after August 22, 2011.

By Federal Register Notice 82 FR 32934 dated July 18, 2017, NRC issued final rule and amended the regulations to require implementation of ASME Code Case N–770–2 "Alternative Examination Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds Fabricated With UNS N06082 or UNS W86182 Weld Filler Material With or Without Application of Listed Mitigation Activities Section XI, Division 1," instead of ASME Code Case N–770–1, subject to the conditions specified in paragraphs (g)(6)(ii)(F)(2) through (13) of Section 50.55a, Title 10 of the Code of Federal Regulations.