The LIFE HUELLAS project includes the development of two monitorign actions, transversely to the technical actions. They were designed to evaluate and to measure the environmental and socio-economic impact due to the implementation actions of the project, by defining specific indicators. The project will test, by running these actions, the effective contribution of the project to the environmental problem targeted: the mitigation of the impacts of Greenhouse Gas Emissions (GHG) and in water resource during the implementation phase in a railway construction work. Both of them are beginning today.