Radon measurements at ground level are a useful tool for the study on atmospheric stability or mixing conditions. Radon concentration in the atmosphere was measured in Milan over a continuous four-year period from 1996 to 1999. In the town area pollutants emitted during late evening and night hours by motor traffic as well as by industrial plants accumulate at low height concurring with radon accumulation in the Nocturnal Stable Layer. In years
1998-1999 radon measurements were taken in Landriano, an area located 30 km south of the town. In Lombard plain there are numerous huge plants, thermoelectric power stations burning by methane and carbon, oil refineries; moreover other plants are being carried out. With the aim to control the contribute of these plants to air pollution, it is important to know atmospheric stability and turbulence conditions. Landriano is only few kilometres from the thermoelectric power station in Tavazzano. In this
paper the results of measuring campaigns as well as the comparison of radon concentrations between the two sites surveyed are reported. The general criteria of the
measurements, the interpretative models of radon concentration in the atmosphere are discussed
