Spatial and temporal variation of respirable particles around a surface coal mine in India

Abstract

People living around surface mines are exposed to enhanced respirable particle level. Not many studies are available that evaluated the contribution of mining to it. The paper presented the result of study that investigated spatio-temporal variability of particle concentrations around a surface coal mine in eastern part of India. Particle concentration and concurrent meteorological parameters at 24 locations were measured along four sections from the mine boundary up to 500 m using an aerosol spectrometer and portable weather station. SPSS 20.0 was used for statistical analysis. Average PM10, PM2.5 and PM1 concentration varied in the range 212.67 ± 168.76–524.46 ± 137.57 μg m−3, and 89.53 ± 77.62–297.41 ± 107.10 μg m−3 and 66.22 ± 58.05–246.66 ± 84.26 μg m−3 respectively. This is equivalent to 2.74, 1.34 and 2.77 times the background concentration of PM2.5-10, PM1-2.5 and PM1 respectively. Respirable particles up to 500 m from the mine comprised of 27–73%, 8–12% and 18–61% of PM2.5-10, PM1-2.5 and PM1. During peak production period, the concentration of respirable particles around the mine increased by a factor 5–15 of the average concentrations. Distance and meteorological parameters explained up to 55% of the variability of particle concentration. Present Indian norm to allow an ambient PM10 concentration of 250 μg m−3 at a distance of 500 m is not met, in spite of the study mine is only 10 years old. Extremely limited literature suggests that more studies are required for better understanding and evaluation of mining contribution to the local PM level.