European and national legislation with regards to the different steps in a phytoremediation approach for metal-contaminated land
Résumé
When applying phytotechnologies for management of metal-contaminated land, many questions are raised with regard to legislative issues. Within the REJUVENATE and GREENLAND projects we try to answer them using a flow approach in which each step when considering and applying phytotechnologies is examined: (1) describing the land status and use, (2) planting/sowing, (3) growing, (4) harvesting and (5) processing the crops, and (6) using the remainders. The focus is on European legislation as a basis for national rules (Directives) or as directly enforceable (Regulations), followed by legislation of the Member States and then, if relevant, regional legislation. Strategic communications of the Commission and proposals for new legislation are considered only when it is probable that these will become formal obligations in the near future. National legislation has been assessed in detail for all countries represented within the GREENLAND project. In the first step, the status and use of the land, and the implications with regards to soil threshold values and the use of crops are defined. In the second step (planting/sowing), international regulation on crop selection, and more specifically on invasive and exotic species, and genetically modified organisms, as well as on soil management, e.g. soil amendments for stabilisation versus the enhancement of ‘bioavailability’ are considered. With regards to step three (growing), the principles of good agricultural practice are checked, e.g. concerning the use of pesticides. The classification of the harvested crop (step four) based on European and national legislation is complemented with an expert view. For the fifth step (processing), we focus on energy conversion of the biomass (e.g. pyrolysis) and on requirements with regards to input and output threshold values. In a final step we concentrate on the use or disposal of the remainders which contain metals in increased concentrations, such as the biochar. The result of a complete analysis of legislation applicable throughout the entire phytoremediation cycle allows us to provide an objective overview to policy makers and regulators, who are now often overwhelmed and maybe even misled by the whole range of potentially related legislation.