In Europe, Health Impact Assessment (HIA) is a consolidated practice aimed at predicting health impacts supporting the predisposition of plans and projects subjected to authorization procedures. In Italy, further developments are needed to harmonize the practice and consolidate methodologies in order to extend the HIA application in different fields. The recent HIA conducted in Val d'Agri (Basilicata) on the impacts of a first crude oil treatment plant represents an opportunity to illustrate its tools, methods and fields of application. In this experience, participation methods in impact assessment have been adapted to the context, emphasizing aspects of ethics, equity and democracy. Environmental and epidemiological studies were included in the HIA Val d'Agri in order to characterize the environment and assess the health status of the resident population. On the basis of the results public health recommendations have been elaborated, shared with the stakeholders and shared with local and regional administrators. The experience in Val d'Agri introduces elements of reflection on the potential of HIA at local level in order to support the public health and the environmental control systems in the area, as well as planning based on preventive environment and HIA.