Assessment of air pollution around coal mining area: Emphasizing on spatial distributions, seasonal variations and heavy metals, using cluster and principal component analysis

Jharia Coal field (JCF) in Jharkhand is the richest coal bearing area in India, which contains large quantities of high grade coking coal. The conventional coal fuel cycle is among the most destructive activities on the earth, threatening the health, polluting the air and water, harming the land, and contributing to global warming. The variations in air quality in terms of sulfur dioxide (SO2), nitrogen dioxide (NO2) and particulate matter around JCF were evaluated over the period of 2010 and 2011 at five sites during different seasons. Air pollution index (API), calculated on the basis of suspended particulate matter (SPM), SO2 and NO2 concentrations was highest near the coal mining area. The ambient concentrations of heavy metals (in PM10) also showed significant temporal and spatial variations at different sites around coal mining areas. Pollutants dispersion and spatial variations were explained by the use of cluster analysis (CA). Multivariate statistical analyses were adopted including; principal component analysis (PCA) to identify the major sources of air pollutants in the area. The mean concentrations of heavy metals in PM10 were found in the order of Fe>Cu>Zn>Mn>Pb>Cr>Cd>Ni. The major sources contributing to air pollution in Jharia were coal mining related activities and active mine fires, and secondarily vehicular emissions, while wind–blown dust through unpaved roads also contributed to some extent.