Priorities List of contaminated sites: a new relative risk assessment procedure

This paper presents a methodology (SER-APHIM) developed to prioritize efforts into investigation and/or remedial actions at contaminated sites at regional scale (Lombardy Region – Italy). The approach is a two-tiered procedure based on the "source-pathway–receptor" paradigm. Tier 1 (SER – Short Environmental Radar) is a screening tool that run with very few site-specific data and leads to a list of critical sites to sort by using Tier 2 (APHIM - Assessment of Priorities for Human health and environmental IMpacts). Tier 2 needs more detailed information about sites and their surrounding areas, including contaminant concentrations in primary sources and secondary sources, geology, hydrogeology, data from a Geographic Information System (GIS) developed for the purpose (which relates the georeferenced sites and their surrounding areas to regional cartography and census data providing climate conditions, land use, natural resources, hydrographic networks and human receptors). Tier 1 application resulted in a list of 50 sites affected by primary sources, polluted soil or groundwater; sufficient data were available only for 43 sites, which were sorted out by Tier 2.