Relative risk assessment in support of the management of potentially contaminated megasites

The relative risk analysis is a screening tool implemented to assess sites affected by actual or suspected contamination and suggest priorities for further actions (characterization, risk assessment, remediation, etc.). Its purpose is to provide technical assistance in the identification and prioritization of sites, which may represent a risk (high, medium, or low) according to their current or potential adverse impact on human health and/or the environment. This tool is relatively simple and applicable to all sites with a limited investigation, such as abandoned large areas (megasites) that are suspected to be contaminated. For these reasons, it can be a very useful tool in environmental policy supporting decision makers involved in the megasites revitalization in the sustainable local or even regional planning process. Megasites management is a very complex process for many features, such as a possible occurrence of multiple contamination sources, general lack of information, multiple site owners/stakeholders/end users, economic and planning implications at all relevant (regional and local) levels. At the same time, megasites may represent considerable environmental and health risks as well as an opportunity for sustainable local and regional development. This article presents a relative risk model as an innovative and simple approach that can be applied to potentially contaminated large areas for recognition and management of “critical” sub-areas, requiring characterization actions, and “not-critical” sub-areas, where redevelopment can start more easily and faster.