Engineering ethics is a complex hierarchical system consisting of an individual, professional and organizational ethics. It is, therefore, important to recognize the interrelated nature of them, and select the adequate contents according to the aim of engineering ethics at universities. This report describes an empirical learning approach, towards engineering ethics through an environmental engineering program based on field works for freshmen where numerous facts, roles and responsibilities coexist across several fields. We found that the program helps students understand the uncooked but attractive themes, thereby the hierarchical aspects of engineering ethics through role play and proposal for solutions. We also recognized that the proactive and challenging mind raised in this program would be carried on to the following engineering ethics course for sophomores.