Microbial adaptation and community dynamics in a former uranium mining and milling site Environmental pollution by toxic metals and radionuclides is a still growing global problem caused by the increasing need in industrial processes such as metallurgy mining and fertilizer production. Furthermore does the increasing salinity of soils by mismanagement of agriculture and industrial waste waters impose a big environmental thread. Therefore bioremediation provides an environmentally friendly and cost efficient way to counteract both. Bioremediation is the process by which living beings such as plants and microorganisms are used to remediate or reduce harmful contaminants from the environment. Therefore various bioremediation methods e.g. in situ biostimulation and bioattenuation or ex situ bioreactors have been developed. Bioremediation approaches are especially valuable for large low contaminated areas such as former uranium mining sites. It is necessary to understand the local environmental parameters as well indigenous microbial community to increase the efficiency of in situ bioremediation approaches. Therefore the microbial community as well as soil and water parameters of a former uranium mining and milling site in Germany were analysed in this study. Results show that the community was dominated by Acidobacteria Chloroflexi and Proteobacteria as well as the fungal phyla Ascomycota and Mortierellomycota. Furthermore typical soil bacteria including phyla such as Firmicutes and Verrucomicrobia were found. Additionally various classes typically found in saline environments were shown. Thus it can be concluded that the co stress by high salt and metal concentrations led to an adapted microbial community including typical members from both environments. The investigation revealed in combination with soil and water analysis showing high salt especially sulphate and metal concentrations an influence of the community structure by remediation processes.