The purpose of the present study is to describe the pattern of pollutant dispersion in the neighbourhood of the thermal power station-II in Neyveli. Neyveli Lignite Corporation houses two mines and two thermal power stations. Thermal power station-II is designed for 7 numbers of boilers each producing electricity at 210 MW, using lignite as the fuel. Gaussian diffusion equation has been used for predicting ground level downward concentrations. Meteorological data collected for a period of one month was chosen for predictions. A critical case was identified for assessing maximum ground level concentrations of SO2 at downward locations under various combinations of wind speeds and atmospheric concentrations. It has been observed that SO2 isopleths for assessing adverse meteorological situations would determine future expansion prospects of thermal power stations at Neyveli.