Feasibility study on the application of solid state tracks detectors for fast surveys of residual alpha contamination in decommissioning activities

A feasibility study concerning the application of Poly-Allyl-Diglycol Carbonate (CR-39™) solid state tracks detectors for fast survey of residual alpha contamination has been carried out at Casaccia Research Center, as a joint effort from ENEA, Sogin, and Sapienza University of Rome. The main target of the activity is to develop and set up a fast and economic method for assessing the presence of residual uranium, plutonium, and/or mixed oxides (MOX) traces on walls, floor, furniture, and small objects (PC-displays, keyboards, tools, etc.) of hot laboratories under decommissioning. The key idea is using CR-39™ foils for cladding surfaces under investigation for recognizing the typical uranium and plutonium clusters originated by alpha particles interaction with CR-39™, that are clearly distinguished from the tracks originated by radon decay products. Results of experimental tests have given a clear picture of alpha tracks clusters originated by plutonium sources, while radon decay products gave uniform alpha tracks' distribution.