To be useful to project managers, real options analysis (ROA) must capture the unique characteristics of individual projects and, at the same time, remain tractable and intuitive. However, real-world projects are often complex and contain multiple sources of uncertainty. To address this, ROA must adapt its framework to the specifics of each project to reflect its key sources of flexibility. We develop a decision model that incorporates the relative contribution of each uncertainty factor, arising from changes in the external environment, to the evaluation of the CSR investment option. This paper undertakes an analysis of an oil development project of the French multi-energy company TotalEnergies in Uganda, and more specifically the decisions made by the CEO during three key periods between 2012 and 2021. For each of the three periods, we examine the magnitude of the real option value drivers and their joint impact on the firm's decision. Our analysis refines the criteria for CSR investment choices, defines its methods and its evolution over time.