This doctoral thesis analyzes – in the light of Constitutional and European principles – the article 253 paragraph 4 of the Environmental Code (d.gls. 152/2006), that, according to the interpretation generally accepted, allows the Public Administration to act against the “innocent” landowner until the amount of the fair value of the site, as it results after the clean-up procedures. Indeed, the Environmental Code obliges the responsible of the land contamination to the reclamation, but it provides for the reclamation the Administration, if the responsible does not arrange it or he is not identified or the landowner or the other person interested does not arrange it. In this case, the public reclamation costs are secured by a special lien ...