New Reactors and New Engineering Programs for Motor-Operated Valves

Abstract

Several new reactors are currently under construction in the USA. Based on current construction schedules, Watts Bar 2 will be the first new reactor to go online for commercial generation since Watts Bar 1 was issued its operating license in 1996. New engineering programs will be going online with new reactors like Watts Bar 2. The startup of these new engineering programs is not without its own set of challenges. One of the programs has undergone a significant transformation since the last nuclear power plant started commercial operation in terms of industry implementation methods and regulatory requirements. In 1996, the NRC issued Generic Letter 96-05 to communicate issues related to periodic verification (PV) of motor-operated valves (MOVs) and to request action by operating commercial power reactors to establish an MOV PV program. Subsequently, the regulations were revised to include a requirement to have an MOV PV program in Title 10, “Energy,” of the Code of Federal Regulations (10 CFR) 50.55a(b)(3)(ii). Generic Letters 89-10 (on MOV surveillance and testing) and 96-05 have been closed and today stand as historical references. Their provisions do not directly apply to new reactors, but there are many lessons available from MOV PV programs at operating sites in terms of safety, implementation, and cost. There is only one consensus standard available to describe the requirements for an acceptable MOV PV program. This is contained in the ASME’s Operation and Maintenance of Nuclear Power Plants (OM Code) as Mandatory Appendix III. The U.S. Nuclear Regulatory Commission (NRC) previously endorsed this approach as a Code Case and is preparing a proposed change to 10 CFR 50.55a to incorporate by reference the ASME OM Code edition that includes Appendix III. This paper conveys the technical complexities and financial concerns faced by plant staff in making the right technical decisions for new program implementation at a new reactor in the USA. Paper published with permission.