Licensing and Deployment of Advanced Reactors

The deployment of advanced reactors of the type proposed for Generation IV will require a new strategy for licensing and demonstration. One of the requirements for NRC certification is that for technologies, for which there is not a regulatory history or an experience base, demonstration plants are a requirement. The current regulatory process as codified 10 CFR Parts 50, 51 and 52 has to be met by law. This process is largely focused on the light-water reactor technology and would make introduction of these new reactor technologies very difficult. What is required is a technology-neutral regulatory regime that will allow the timely licensing of advanced reactor technologies. One of the difficulties that the introduction of new technologies brings is that if they are truly new, the regulators are not typically engaged in the development of the technology, which greatly hampers their ability to perform a review. What is necessary is the development of a new approach in which the regulator can participate in the development of the technology as well as the development of a risk informed regulatory process in which high-level safety goals can be demonstrably attained. In addition, since these new technologies will require a demonstration, there needs to be an efficient process in which the regulator is engaged early in the process, to allow for learning about the technology, and participating in the specification of tests to satisfy the technical and safety needs of the regulators so that they can make a finding of reasonable assurance of public health and safety. What will be proposed is a process whereby new technologies can be deployed in a reasonable period of time, consistent with an independent regulatory review, applying new risk-informed principles to guide the regulator and the designer to assure that the fundamental safety functions can be realized in a technology-neutral approach. This is particularly important since many of the proposed Generation IV technologies include concepts such as high temperature gas, liquid metals such as sodium, lead and lead bismuth, molten salt reactors and even vapor core reactors. These will surely challenge the existing regulatory system if changes are not made. 1. BACKGROUND Under the existing regulatory structure, the applicant for an advanced reactor must demonstrate compliance to all of the regulations as written or seek exemptions to those particular regulations. As early as 1988, General Electric proposed (Ref. 1) a new process for certifying advanced reactors by calling for a new appendix to Part 50 to address the differences in licensing technologies that are not water based. In 1988, General Electric was seeking to license an advanced liquid metal breeder reactor called PRISM. More recently, Exelon has developed a Proposed Licensing Approach for Pebble Bed Modular Reactor in the United States (Reference 2) that points out the difficulties in the process of attempting to comply to current regulations with non-water technologies. They have spent a considerable amount of time identifying which regulations might be applicable to the Pebble Bed Modular Reactor (PBMR), and for those that are not applicable, they need to justify why not and request an exemption to that particular regulation. In addition, the General Design Criteria are cited in the regulations which identify certain high-level objectives. These 64 General Design Criteria also need to be addressed in terms of their applicability. Once those have been addressed, the implementing regulatory guides also have to be reviewed and justifications need to be made as to why the prescriptive implementation of the general design criteria for a new and advanced reactor are either applicable, partially applicable or not applicable. Most recently, the Nuclear Energy Institute proposed a new licensing approach to all reactors (Ref. 3) by calling for a risk-informed performance based regulatory framework for all types of reactors by advocating a rulemaking to promulgate a new Part 53 that would greatly simplify and focus regulations on safety significant aspects of nuclear reactor design and operations. All these activities are based on risk informed processes to improve the overall regulatory process. While the NEI initiative provides an approach to making licensing basis decisions, it does not address the challenge of introducing new technologies. Under any licensing scenario, the task facing a potential developer of an advanced reactor is quite