In this paper, the analysis of the vegetation growing on the waste dump Siechnice was carried out. On the basis of phytosociological relevès, the plant species were determined. It was shown that vegetation identified on the waste dump is similar to the plants growing around this area. What is more, ecological succession of Urticaceae was observed, which proves succession of plants preferring alkaline soils. In addition, the ecotoxicological tests did not show the contamination impact of soil samples. We recorded only a slight inhibition of growth of A. sativa (in the shoot length in lower part of dump).