Soil chemical contamination from heavy metals, chlorinated compounds, hydrocarbons and its derivatives is an environmental emergency which remains to a great extent unresolved. The recent update of the indicators of the state of remediation of European contaminated sites, carried out by the Joint Research Centre shows 650 000 registered sites in the inventories of the 28 EU Member States, where remediation processes have been completed or are currently in progress. Over 76000 new sites have been listed since the previous survey in 2014. More than 65 500 sites are presently undergoing corrective measures or receiving post-intervention support. Bioremediation shows significant economic and practical advantages among all possible reclamation technologies compared to excavation and off-site disposal. In the past decades, biological techniques have proved effective, however, their use is still quite limited.They are indeed applied in less than 20% of cases in Europe with different rates in the various countries.
The LIFE-BIOREST project aimed to provide a viable method that uses fungal and bacterial strains for the in situ bioremediation of contaminated sites. The project partners aimed to demonstrate their new method to bioremediate soil from a site at Fidenza in northern Italy, reducing the presence of contaminantswithin threshold limits for residential and public use while restoring the ecological functions of the site. The project also aimed to assess the cost-effectiveness and replicability of the remediation methods and demonstrate the feasibility of scaling up to industrial level the production of microorganisms used for bioremediation. The project will produce bioremediation guidelines, enabling the techniques to be transferred to other locations.
The LIFE BIOREST project demonstrated an innovative method for the bioremediation of contaminated soil to a level compatible with residential and civil use, at a site in northern Italy. It is based on microorganisms (bacteria and fungi), agricultural by-products and plants, to restore contaminated soil and revegetate it.
Project partners (in Italy, France and Spain), optimised and tailored protocols for the bioremediation of the test site, based on a combination of microbes, with improved degradation abilities towards PAHs and mixtures of BTEX. They validated and scaled-up the production of microorganisms to treat polluted sites, guarantee an efficient bioremediation of a defined demonstration area of about 400 m3 in the former Carbochimica site in Fidenza. The project team re-established vegetation on the treated soil showed the possibility of cultivating different plant species and produced chemical, microbiological and eco-toxicological indicators to monitor soil quality restoration.
The project’s study of contaminated sites analysed registries produced by Italian regions, and data from regional agencies (e.g. ARPA) and the Environment Ministry. This formed the basis for a database, which is the first national instrument for the census of polluted sites in Italy, classified by region, source and type of contaminants - with a special focus on hydrocarbon pollutants. Over 20 000 sites were mapped, of which 9 487 require remediation, including 2 119 sites contaminated by hydrocarbons (oil and derivatives) that are suitable for the project’s bioremediation approach, equivalent to 22% of Italy’s contaminated sites.
The experience gained led to the elaboration of guidelines to exploit indigenous microorganisms to remedy contaminated land to reduce soil pollutant concentrations, which will enable the technique to be replicated in other contaminated sites. Associated beneficiary UNITO is storing all the fungi used in Fidenza site's bioremediation in its Fungal Collection, affiliated to the World Federation Culture Collections (WFCC), while USCS is storing the bacterial strains in its collection.
The project’s dissemination, educational, awareness-raising and engagement activity successfully reached the general public, students, researchers, teachers, policymakers, stakeholders, and entrepreneurs, through especially-tailored content and targeted messages.
Direct environmental benefits included the removal of hydrocarbons (e.g. 300 mg/kg of hydrocarbons removed in 60 days of monitoring), along with faster pollutant degradation. At the end of the treatment, hydrocarbon pollutant removal was 38% higher than in the control plots, and at the final stage toxicity was halved in comparison with the control.
The project contributed to the implementation of the EU Soil Thematic Strategy by restoring degraded soils through a cost-effective and scalable bioremediation approach; the EU Biodiversity Strategy for 2020 (Target 2) by providing an in situ bioremediation solution that can enhance biodiversity and restore ecosystem functions; and the 7th Environment Action Programme objectives by providing a means to return contaminated soils to productive use using a protocol that valorises waste biomass.
The project’s socio-economic study, based on interviews with the general public, researchers, industry and policymakers, raised awareness and helped address sustainable behaviours and citizens' perceived environmental concerns. The project’s protocol ensured cost-efficiency, based on the production of inexpensive microorganisms. The calculated average cost of treatment was €150/ton, mainly accounted for by operating costs, with the costs of bio-augmented bacteria production being around €2-20/ton.
Further information on the project can be found in the project's layman report and After-LIFE Communication Plan (see "Read more" section).