Environmental remediation of polluted sites

According to art. 242 of Legislative Decree 152/2006 as amended., the ordinary remediation procedure provides:

1. Notification of the contaminating event within twenty-four hours to the competent authorities: upon the occurrence of an event that is potentially capable of contaminating the site, the polluter shall implement, within twenty-four hours, the necessary prevention measures and shall immediately notify them pursuant to and in the manner referred to in Article 304, paragraph 2. The same procedure applies to the identification of historical contaminations that may still entail risks of aggravation of the contamination situation.
2. Preliminary investigation of the parameters subject to pollution: the polluter, having implemented the necessary preventive measures, carries out, in the areas affected by the contamination, a preliminary investigation of the parameters subject to pollution and, if he ascertains that the level of Contamination Threshold Concentrations (CSC) has not been exceeded, provides for the restoration of the contaminated area.
3. Characterization of the site through a special Characterization Plan: if the preliminary investigation ascertains that the CSCs have been exceeded, even for a single parameter, the person responsible for the pollution shall immediately inform the Municipality and the Provinces competent for the territory with a description of the emergency prevention and safety measures adopted; in the following thirty days, it submits to the aforementioned administrations, as well as to the territorially competent Region, the Characterization Plan with the requirements set out in Annex 2 to Part Four of Legislative Decree 152/2006 as amended, which describes the environmental matrices involved and the nature of the contamination.
4. Approval of the Characterization Plan: within the following thirty days, the Region, having convened the conference of services, authorizes the Characterization Plan with any prescriptions.
5. Risk analysis to determine CSR values: on the basis of the results of the characterization, the site-specific risk analysis procedure for the determination of Risk Threshold Concentrations (CSR)  is applied to the site.The criteria for the application of the risk analysis procedure are established in the manner indicated in Legislative Decree 152/2006 as amended.
6. Presentation of results Risk analysis: within six months of the approval of the characterization plan, the responsible party shall submit the results of the risk analysis to the Region. If the results of the risk analysis procedure show that the concentration of contaminants present on the site is lower than the CSRs, the Conference, with the approval of the risk analysis document, declares the procedure concluded. In this case, the Services Conference may prescribe the carrying out of a monitoring programme on the site regarding the stabilisation of the situation found in relation to the results of the risk analysis and the current intended use of the site.
7. Operational Remediation Project (POB) or Permanent Safety Measures (MISP), if the CSR values are exceeded: if the results of the risk analysis procedure show that the concentration of contaminants present on the site is higher than the risk threshold concentration (CSR) values, the responsible party submits to the Region, within the following six months from the approval of the risk analysis document,  the operational project of the remediation or safety interventions, operational or permanent and, where necessary, the additional environmental remediation and restoration measures, in order to minimize and bring back to acceptability the risk deriving from the state of contamination present on the site.
8. Approval of the project: the Region, having obtained the opinion of the Municipality and the Province concerned through a special Services Conference and having heard the responsible party, approves the project, with any prescriptions and additions within sixty days of its receipt.

A simplified procedure (Article 242-bis) is also provided for voluntary interventions at the expense of the interested party.

What is the characterization plane and what does it mean?

The Characterization Plan is a technical-design document that systematically describes the contamination phenomena that affect the environmental matrices (soil, subsoil, groundwater, etc.), providing all the information necessary for the subsequent safety and/or remediation of the site.  

The document contains a detailed description of the activities to be carried out, both in the field and in the laboratory, for the correct environmental characterization. In particular, the proposer is required to include the technical specifications for the execution of the activities (sampling procedures, field measurements, methods of identification, storage and transport of samples, analytical methods, etc.) which, once approved by  the competent authorities, before the start of the works, constitute the applicable reference protocol for site characterization.

When and in which cases is a risk analysis of contaminated land carried out?

Risk analysis can be applied before, during and after environmental remediation of polluting sites or safety measures. The regulatory structure refers to two threshold criteria for intervention:

• the first (CSC) to be considered a value of attention, beyond which it is necessary to carry out a characterization and
• the second (CSR) which identifies the acceptable residual contamination levels, calculated by risk analysis, on which to base the safety and/or remediation interventions.

The remediation of a polluted site is aimed at eliminating pollution of environmental matrices or at bringing the concentrations of pollutants in soil, subsoil, groundwater and surface water, within the contamination threshold values (CSC) established for the intended use or the Risk Threshold Concentration (CSR) values defined on the basis of a Risk Analysis methodology conducted for specific sites on the basis of the criteria listed in Annex 1 to Part Four of Legislative Decree 152/2006 as amended.

What are the parameters for classifying the technology to be used for the environmental remediation of polluting sites?

The choice of the solution to be adopted takes into account the process of assessing the environmental benefits and the sustainability of the costs of the various applicable techniques, according to the criteria below, also in relation to the intended use of the site. In particular, the definition of a programme for the permanent remediation/safety and environmental restoration of a polluted site is carried out on the basis of:

• intended use of the site;
• objectives to be achieved;
• purpose and principle of processing (treatments for destruction, mobilization aimed at recovery and treatment, inertization or containment, excavation and disposal on an appropriate site);
• nature of the process (chemical-physical, thermal, biological treatments);
• matrix (unsaturated, saturated soil and/or groundwater);
• handling of the contaminated matrix (in situ or ex situ, and, in the latter case, on site or off-site).

Some examples of treatments are: biopiles, bioreactors, landfarming, phytoremediation, bioventing, biosparging, natural attenuation, washing, vapor extraction, air sparging, permeable reactive barriers, product recovery, desorption, other.