Remediation of contaminated sites in Italy: state of the art of technologies and plannig & design criteria

Remediation of contaminated sites in Italy has been so far governed by the so-called Ronchi Decree (Ministerial Decree 2/97) and by the subsequent Ministerial Decree 471/99, which laid down detailed procedural and technical provisions. Most of the site remediation projects conducted in Italy have fallen under the scope of the above Decrees. This legislation was recently revised by Legislative Decree no. 152 of 3 Apr. 2006 (hereafter called "Decree 152/2006"), consolidating and superseding all previous laws and regulations on environmental matters (including general legislation on water protection, namely Legislative Decree no. 152 of 11 MayI999). On the other hand, Decree 152/2006, including provisions on remediation of contaminated sites, is already being overhauled. Against this background, it is useful to make a critical analysis of the seven years of application of the prior legislation (Ministerial Decree 471/99), in order to derive suggestions for the more technical aspects of the ongoing revision. The following analysis considers both remediation and emergency containrnent of contaminated groundwater and soil, focusing on the interaction between the legislative-regulatory framework and the consequent technological choices and, namely, on their planning & design. The analysis is of a merely qualitative nature and hinges on the direct experience of the Authors, acting as remediation specialists and technical and scientific consultants. Therefore, the analysis solely reflects their personal opinions. Table 1 gives a qualitative overview of the technologies used in Italy for rehabilitating contarninated sites. The Table shows that most of the technological options available in the state of the art have been used. Largely dominant among them were ex-situ technologies, especially excavation and disposal for soil and Pump & Treat (P&T) for water. These approaches, whose use was at tirnes inevitable, were not particularly effective in terms of environrnental sustainability. Indeed, in both cases, the contarninated resource is not restored to its original or potential uses. Even if encouraging progress has recently been made, the use of in-situ technologies has remained marginal and should thus be intensified. Among the latter technologies, mention is to be made of those largely used in other countries, such as permeable reactive barriers, aerobic and anaerobic bioremediation and in-situ chernical oxidation.