Field scale phytoremediation of soils contaminated with heavy metals and radionuclides and further utilization of the plant residues

Phytoremediation is applied to a site in the former uranium mining area of Ronneburg in Eastern Thuringia, Germany, slightly contaminated with heavy metals and radionuclides (HM/R). In a joint research project, remediation of HM/R-contaminated sites is investigated and concepts for the subsequent utilization of the contaminated plant residues are developed. To minimize HM/R-accumulation in soil and to reduce groundwater contamination a combination of phytostabilization and phytoextraction methods is applied and lysimeter experiments are performed to demonstrate the reduction of seepage water rate and load. The final utilization of HM/R loaded plant residues after harvests was studied by biogas and ethanolic fermentations and by combustion of the plant material. The fate of HM/R in the different by-products was investigated.