The main aim of the study was to verify migration characteristics and remedial efficiency of two types of nZVI, NANOFER 25S and NANOFER STAR, using advanced procedures for monitoring NPs and vertical stratification of contamination. NANOFER 25S is an aqueous dispersion of nZVI particles with a surface modification based on the combination of a biodegradable organic and inorganic stabiliser and NANOFER STAR is a Surface stabilised, Transportable, Air-stable and Reactive (i.e. STAR) powder, meaning it is much easier to store and process compared to the original pyrophoric powder. Spolchemie is one of the leading synthetic resin manufacturers in Europe, located at Usti nad Labem, Czech Republic in the heart of Europe. The plant started to produce resins and freons based on perchloromethane and tetrachloroethene in the middle of the last century. The production, treatment, storage and distribution of these various raw materials and products has led to extensive contamination by chlorinated ethenes and methanes, which in many cases have dispersed widely from the original source areas.