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Enhancement of the radon activity concentration in Crotone indoor environments due to the employment of TENORM as inert material
Nicolino A., Ligato M.R., Ferraro M., De Luca F., Procopio S.
The Rn-222 in indoor environments may be due to several factors: exhalation from the ground, the soil, building materials and NORM. The processing of NORM may result in the production of TENORM. In this framework, remarkable is the case of Crotone where several chemical factories were specialized in the treatment of phosphorite rocks, rich of U-238 and Th-232. Because of their mechanical properties, in the recent past, the TENORM residues have been employed in the construction of roads, dwellings, warehouses, and public buildings. We propose a down-scaled model of a house, whose crawlspace is filled with TENORM harvested in Crotone. We monitored the indoor environmental radioactivity by using both active and passive device and observed an important increase of the Rn-222 activity concentration, whenever TENORM residues are inserted. Finally, the results of the model were compared to a real use case, a warehouse in Crotone. A good agreement was found between the results of the environmental screening of the warehouse and the predictions of the model in terms of Rn-222 activity. This indicates that Rn-222 can actually be used as a TENORM precursor in order to map the phosphorite contamination.