Dewatering e bonifica dell’ area ˝ex Whitehead Motofides˝ (Pisa, Italia)

Abstract

In 2007 the activities for the remediation of the “ex-Whitehead Motofides area” (in Marina di Pisa, Italy) started. In order to allow the contaminated soil excavation in dry conditions a dewatering system was necessary. The water pumped through this system was then treated in an adequate plant. Acque Industriali realized and managed the whole system. The dewatering system was made of suction pins fixed to a depth of 5.5 m, connected by a junction manifold to the suction and booster vacuum assisted pump, which allowed the groundwater release toward the plant. The treatment plant, entirely designed by Acque Industriali and called ITAM (Impianto di Trattamento Acque di Falda Mobile, which means movable groundwater treatment), was realized and set up at the end of 2008. It consisted of a pre-treatment section, made of reinforced concrete, prefabricated nitrogen sweep elements, and a physical chemical treatment plant, in a continuous loop, completely made on skid. The plant, with 25 m3/h of maximum potential, was able to remove possible sedimentable or in suspension material particles from water, iron, manganese, residual organic substances such as hydrocarbons, solvents (chlorinated and not), PCBs, and partly heavy metals. Totally, 98,167 m3 of groundwater were managed in about 25 months of activity. The analytic input and output results confirmed extremely high and satisfactory pollutant removal efficiency. The concentration values of the pollutants, in fact, were always lower than the limits imposed by law.