6.5. Site characterization is an activity undertaken in order to understand the natural features, events and processes at a site (at the present time, in the past and potentially in the future) and to describe adequately their spatial and temporal extent and variability. Site characterization contributes to a comprehensive description of the site, which may include information concerning anthropogenic characteristics (e.g. land use and transport infrastructure for environmental studies). There should be a clear understanding of the context and of the objectives for any site characterization in order to define properly the degree and focus of the site characterization activities that will be necessary. Site characterization will comprise data acquisition (i.e. mensuration, sampling and monitoring) and the interpretation of that data to generate information and knowledge. Site characterization will essentially begin at the earliest stage of the investigation of a site and is expected to become more intensive as the facility development programme progresses through to confirmation of the site and commencement of construction.