ABSTRACT
Photodegradation in situ of 2,3,7,8-tetrachlorinated dibenzo-p-dioxin (TCDD) trapped on the wall surfaces of contaminated homes was considered. Several methods of TCDD disposal have been listed in the special Law for Seveso voted by the Lombardy Regional Government on January 2, 1977. The demolition and disposal of the building itself began after the 2,4,5-trichlorophenol plant had been totally emptied and the residual contamination fixed with paint. The dioxin concentration varied greatly from a few ng/kg of soil to a few mg/kg of soil in the same highly polluted land area, the "A" Zone. Post-reclamation problems include the use of the ex-A area as a park, the control of the two basins, and gradual removal of existing limitations in the use of the low-contaminated B Zone. The dechlorination was a function both of the quantity of gamma rays absorbed by the soil/solvent mixtures and of the type of solvent used.
