Environmental pollution assessment in the suburbs of coalmines in the selected districts of Balochistan, Pakistan

Abstract

Everyone favors quality of an environment basically in terms of soil, water and air. Coalmining fields of Balochistan were evaluated for environmental pollution, recording seasonal variation, and mapping the pollution concentration. Five coal mining fields were selected based on maximum number of functional coalmines and ease of access. Sampling was done for soil (300 samples), water (100 samples) and air (20 samples of PM10) during two seasons i.e. summer (July 2017) and winter (January 2018). Status of soil, water and air was checked through multiple approaches. First, physicochemical analysis was carried out for the selected set of parameters for each of the three environmental mediums. Results were evaluated for seasonal variation in order to investigate the gradual changing effect. The seasonal change is mainly attributed to the natural meteorological conditions and human induced activities (i.e. various coal mining operations) leading to the contamination of site. Pollution indices were incorporated to check the extent and level of contamination. Pollution indices like contamination factor (CF), pollution load index (PLI), integrated pollution index (IPI) and geo-accumulation index (Igeo) were incorporated for soil quality data. Water quality index (WQI) was incorporated for water quality data to determine the overall chemistry and status of water for drinking purposes. Analyzed data for all the three environmental mediums along with ArcGIS tool was used to construct thematic maps i.e. interpolation distance weight (IDW) to visually demarcate the significant distribution of variables and compared the obtained results values with the WHO standards (2011) to depict the overall health of environment around coalmines. Majority of parameters crossed the safe permissible limit of WHO standards. Moreover, principal component analysis (PCA) and Pearson’s correlation matrix analysis was carried out by using a statistical software i.e XLSTATE, for the data analysis in order to identify the source of pollution and correlation among the variables. Results suggested a significant variation observed during both the seasons and the main driver was the precipitation patters and other climatic factors. Computation of pollution indices for soil and water variables concluded that both the mediums were moderately contaminated. However, in comparison to the control site all the environmental mediums were severely deteriorated. Main reason of this significant deterioration was because of the over exploitation of coal mines and mining activities. Spatial analysis concluded that all the parameters selected for environmental variables were xiv significantly distributed across the selected sites. Among the selected study sites, Khost and Sharagh were the most polluted sites. The current investigation provided a comprehensive picture of the status of environment in and around the coal mines distributed across the four districts of Balochistan.