ABSTRACT
The concentration of population in big cities, traffic crisis and air pollution problems have urged authorities to lunch heavy subway projects to resolve transportation issues and bring more sustainability to the built environments. Considering factors such as complexity, size and challenges of metro line projects along with their budgets and schedules, that put them in the category of heavy construction projects, the way these projects interact with a whole urban society during the design, construction and operation phases, and the way they change the cities, the success of these projects is highly dependent on applying sound project management systems and at the very heart of that, a strong formulation and implementation of a dynamic risk management methodology. This is to scan the future of a project and plan for it ahead. The increasing number of researchers in the field of risk management and the high demand for risk analysts and managers by big companies around the world nowadays are good proofs of the vital role of effective risk management. In this research, while introducing the ATOM (Active Threat and Opportunity Management) risk management methodology, a brief review is given on how the risks of the EPCandF contract of the middle section (7.1 km) of the 32 km Tehran metro line 6 were identified and ranked based on this methodology with responses to its top risks (Hashemi et al., 2021). This laid the foundation for a comprehensive implementation and customization of the ATOM methodology in the ongoing 10 km Tehran-Eslamshahr subway project as supported by the client. The ATOM comprehensive risk management methodology is an eight-step process including 1. Initiating, 2. Identification, 3. Assessment, 4. Risk response planning, 5. Risk reports, 6. Implementation, 7. Major and minor reviews, and 8. Post-project reviews (Hillson & Simon, 2020).
