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Purpose Coal mining activities are inevitably connected with production of acidic drainage and airborne compounds such as fly ash and bottom ash with high metal content. Soil is a prominent sink for trace elements discharged from anthropogenic sources. Thus, understanding the occurrence, accessibility and ecological risk of trace elements around coal mining areas is of utmost importance in view of implications for environmental health. Materials and methods Seventy-five soil samples from 25 different sites were collected from Jharia coal field (India) and analyzed for pH, electrical conductivity, total organic carbon, and trace elements. For the background values of trace elements, black shale and sandstone were collected from the study area and analyzed for trace element concentrations. Sampled soils were evaluated for the level of soil contamination with respect to average shale concentrations of toxic trace elements in the region and assessed for their ecological risk in terms of enrichment factor, contamination factor, and pollution load index. Interactions among different trace elements and their spatial distribution were analyzed by the use of multivariate approaches. The study also quantifies the potential sources of contamination for each element and their relation with emission source. Results and discussion The average concentrations of Pb, Ni, Cu, Mn, Fe, Zn, and Cd in the soil exceeded the world averages, while Cu and Zn overstepped their respective critical limit in the soil. Enrichment factor values showed that soil near coal mine areas was loaded with Pb, Cd, Cu, Zn, and Ni. The pollution load index and contamination factor suggest that the soils were contaminated by all the investigated trace elements and areas near coal mines were the most polluted. The absolute principal component score technique, combined with multiple linear regression analysis revealed three major factors, coal mining activities/mine fires (40 %), windblown dust (23 %), and crustal (24 %), were responsible for soil trace element pollution in the area. Conclusions Coal mining activities, mine fires, and windblown dust are the chief contributors of soil pollution in the area. Coal mining activities/mine fires are the main contributing sources to soil Ni, Cu, and Cr, while crustal input was mainly represented by Mn and Zn and windblown dust for Pb, Fe, and Cd. High concentrations of trace elements at any site depend on the feasibility and availability of respective pollution sources.

The aim of this study was to investigate the effects of coal mining activities on the community structures of woody and herbaceous plants. The response of individual plants of community to defilement caused by coal mining was also assessed. Air monitoring, soil physico-chemical and phytosociological analyses were carried around Jharia coalfield (JCF) and Raniganj coalfield. The importance value index of sensitive species minified and those of tolerant species enhanced with increasing pollution load and altered soil quality around coal mining areas. Although the species richness of woody and herbaceous plants decreased with higher pollution load, a large number of species acclimatized to the stress caused by the coal mining activities. Woody plant community at JCF was more affected by coal mining than herbaceous community. Canonical correspondence analysis revealed that structure of herbaceous community was mainly driven by soil total organic carbon, soil nitrogen, whereas woody layer community was influenced by sulphur dioxide in ambient air, soil sulphate and soil phosphorus. The changes in species diversity observed at mining areas indicated an increase in the proportion of resistant herbs and grasses showing a tendency towards a definite selection strategy of ecosystem in response to air pollution and altered soil characteristics.

Iron and steel industry is the principal driving force propelling economic and technological growth of a nation. However, since its inception this industry is associated with widespread environmental pollution and enormous water consumption. Different units of a steel plant discharge effluents loaded with toxic, hazardous pollutants, and unutilized components which necessitates mitigation. In this paper, pollutant removal efficiency, effluent volume product quality, and economic feasibility of existing treatments are studied vis-à-vis their merits, demerits, and innovations to access their shortcomings which can be overcome with new technology to identify future research directions. While conventional methods are inadequate for complete remediation and water reclamation, the potential of advanced treatments, like membrane separation, remains relatively untapped. It is concluded that integrated systems combining membrane separation with chemical treatments can guarantee a high degree of contaminant removal, reusability of effluents concurrently leading to process intensification ensuring ecofriendliness and commercial viability.