RS-10-047, Supplemental Information Related to Proposed Alternative to 10 CFR 50.55a Post Weld Heat Treatment Requirements for Piping Replacements (Relief Request No. 1203)

Supplemental Information Related to Proposed Alternative to 10 CFR 50.55a Post Weld Heat Treatment Requirements for Piping Replacements (Relief Request No. 1203)

ML100710476
Person / Time
Site:	Clinton
Issue date:	03/12/2010
From:	Hansen J Exelon Corp, Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-10-047, TAC ME1878
Download: ML100710476 (2)

Text

www .exeloncorp .co m Exelon.

Nuclear Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555 10 CFR 50.55a RS-10-047 March 12, 2010 U. S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, DC 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRC Docket No. 50-461

Subject:

Supplemental Information Related to Proposed Alternative to 10 CFR 50.55a Post Weld Heat Treatment Requirements for Piping Replacements (Relief Request No. 1203) (TAC No. ME 1878)

Reference : Letter from J . L. Hansen (Exelon Generation Company, LLC) to U . S . NRC, "Request for Proposed Alternative to 10 CFR 50.55a Post Weld Heat Treatment Requirements for Piping Replacements (Relief Request No. 1203)," dated May 5, 2009 In the referenced letter, Exelon Generation Company, LLC (EGC) requested approval to use an alternative to the requirements of the 1989 Edition of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code Section XI, Article IWA-4000, for repair and replacement activities at Clinton Power Station (CPS), Unit 1, during the twelfth refueling outage (i .e., C1 R12) . The purpose of this letter is to provide updated information related to this relief request based on the rescheduling of portions of the associated station modification, and to request continued review of this request for use in the thirteenth refueling outage (i.e., C1 R13) .

In this relief request (i .e., Relief Request Number 1203), EGC proposed to use the requirements of Table NB-4622.7(b)-1, "Exemptions to Mandatory PWHT," of the 2006 Addenda of the 2004 Edition of ASME Section III NB for the repair/replacement of piping in the reactor water cleanup system . That piping was initially scheduled to be installed in C1 R12 which began January 11, 2010, and ended on February 5, 2010 . During outage planning activities that occurred late in 2009, it was determined that the installation of portions of this piping would not occur during C1 R12. The piping replacement has been rescheduled to occur during C1 R13, which is scheduled to commence on January 16, 2012. Additionally, unlike C1 R12, which occurred at the end of the Second Inservice Inspection Program (ISI) interval, C1 R13 will occur within the third ISI interval . The code of record for the third 10-year ISI interval at CPS will be the 2004 Edition of the ASME B&PV Code.

Please continue to review Relief Request Number 1203, and evaluate its' suitability for use in the third ISI interval at CPS .

March 12, 2010 U. S. Nuclear Regulatory Commission Page 2 There are no regulatory commitments contained in this letter . If you have any questions concerning this letter, please contact Mr. Mitchel A. Mathews at (630) 657-2819 .

J Manager - Licensing and Regulatory Affairs