Evaluation of radiological impacts from NORM: a case study

In this article an evaluation of the radiological impact for a TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials) waste, coming from a landfill of one of the Italian reclamation Sites of National Interest (SIN), is made in order to assess any possible radiological hazard for the population. The natural radioactivity investigation was performed by using High Resolution Gamma-ray Spectrometry (HRGS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), to determine activity concentrations of U-nat (238U, 234Th, 234−mPa, 234U, 235U and 231Th), Ra-226+ (226Ra, 222Rn, 218Po, 214Pb, 214Bi and 214Po), Ra-228+ (228Ra and 228Ac) sub-chains radionuclides and 40K, and to compare them with clearance levels (CL) reported in the European Commission “Radiation Protection 122-part II”. The Sum Index (SI), i.e. the sum of the radionuclides specific activity normalized to the respective CL, was calculated, in order to investigate about the compliance of the analyzed waste according to the limit set in terms of individual effective dose for the population.