Network-of-Networks Framework for Multimodal Hazmat Transportation Risk Mitigation: Application to Used Nuclear Fuel in Canada

The transportation of hazardous materials (hazmat) is a complex process that continues to receive considerable attention from practitioners and researchers alike. A multimodal system that integrates road and railway networks is often argued as the optimal solution. Given the unique characteristics of each network, the integration of both networks generates an additional layer of complexity attributed to their interdependency. In this respect, the current study utilizes complex network theory to develop a network-of-networks (NoN) framework for multimodal hazmat transportation. Hazmat transportation routes are informed through various measures, including the shortest distance and least vulnerable routes. The case study considered herein applied the developed NoN framework to used nuclear fuel transportation. The analysis results indicate that optimal transportation routes are different for the shortest path and the least vulnerable analysis. These results are expected to inform future hazmat transportation route planning to incorporate more complex and dynamic network characteristics.