Licensing process characteristics of Small Modular Reactors and spent nuclear fuel repository

Abstract

This paper aims to increase the understanding of the licensing processes characteristics of Small Modular Reactors (SMR) compared with licensing of spent nuclear fuel repository. The basis of the SMR licensing process development lies in licensing processes used in Finland, France, the UK, Canada and the USA. These countries have been selected for this study because of their various licensing processes and recent actions in the new NPP construction. Certain aspects of the aviation industry licensing process have also been studied and selected practices have been investigated as possibly suitable for use in nuclear licensing.Suitable features for SMR licensing are emphasized and suggested. The licensing features of the spent nuclear fuel deep repository along with similar features of SMR licensing are discussed. Since there are similar types of challenges of lengthy licensing time frames, as well as modular features to be taken into account in licensing, these two different nuclear industry fields can be compared.The main SMR features to take into account in licensing are:•Standardization of the design.•Modularity.•Mass production.•Serial construction.Modularity can be divided into two different categories: the first category is simply a single power plant unit constructed of independently engineered modules (e.g. construction process for Westinghouse AP-1000 NPP) and the second one a power plant composed of many reactor modules, which are manufactured in factories and installed as needed (e.g. NuScale Power SMR design).The deep underground repository for spent nuclear fuel, such as the one planned to be built to Olkiluoto, Finland, is based on modular design and phased construction. In this case the disposal tunnels, bentonite buffer and backfill and the disposal canisters can be considered as modules. Due to its phased construction the facility has similar licensing characteristics of SMRs.A common licensing process needs to be simple and clear to ensure the feasibility of construction and deployment of SMR's as well as the deep geological repositories.One of the important aspects of nuclear licensing is the compliance to licensing requirements. In a discrete and transparent matter, systems engineering (SE) and requirements engineering (RE) are discussed with the licensing development. The sheer number of licensing requirements is daunting, interconnected in a complex fashion and long-lasting. The process and tools play a critical role in the success of the licensing effort.A few proposed examples of combined SMR and deep repository licensing applications are discussed using SE and RE principles. A synergistic discussion on licensing models, nuclear licensing simplification, as well as international approach in licensing, will be needed in the future. This would be a natural continuation to the collaborative efforts in Europe underway for existing and new large reactors.