The aim of the doctoral thesis was to presente a new pilot scale technology of chemical soil washing. Soil washing with EDTA chelating agent, removed potentially toxic metals (PTMs) from the soil (from 69 to 84 % of Pb, from 22 to 64 % of Zn and from 52 to 70 % of Cd). The novelty of soil washing is separating the solid-liquid phases and simultaneous leaching mobile EDTA PTMs complex in a chamber filter press. After soil treatment the EDTA was successfully recycled up to 76 % with acid precipitation and with alkaline pre-treatment of process solutions, which removed the PTE and all Fe from the EDTA complex. Treated washing solution by electrochemical advanced oxidation processes (EAOP), removed the remaining PTE (up to 99.9 % Pb, 98.9 % Zn and 99.4 % Cd) and EDTA (up to 99.9 %) in the solution with the electrodeposition of metals on the stainless steel cathode. The entire process solution was recycled and used for soil washing/rinsing. The material costs, electricity and consumables, were within the frame of currently available technologies. The best costs of this mode of operation amount to 50.5 Ž per ton of soil for direct disposal of toxic solid wastes and 56.1 Ž per ton of soil for waste stabilization with bitumen and disposal as non-hazardous material.