Geochemical Studies of some Heavy Metals’ Toxicity in Groundwater with their Plausible Sources around Gondwana Supergroup, Wardha Valley Coalfields, Maharashtra

Abstract

The study is designed for groundwater assessment in terms of some sorted heavy metals’ toxicity and their probable source in Wardha valley coalfields, Maharashtra. For both seasons, 45 groundwater samples were collected separately to assess Al, Cd, Cr, Cu, Fe, Ni, Pb and Zn by AAS. Among them, 22 were found contaminated as per BIS (2012) concerning Cd, Fe, Ni and Pb. The major contributors in both seasons were Fe, Zn, Cu and Al. The PCA study has shown sound relationships among Fe-Ni, Cd-Ni, and Al-Cu-Zn. The contamination intensities in various samples indicates that the mining region as a prime cause. The Kamthi and Barakar formations in the study area were considered as a contamination source. The significant role of lower pH environment in enhanced contamination was revealed in the correlation analysis. Accordingly, the probability of acid mine drainage was supposed. The EPMA and SEM-EDS/X studies reveal the presence of sulphide phases in Barakar Formation and sulphur in associated carboniferous strata confirming the source of lower pH. Accordingly, the acid mine drainage was anticipated to be responsible for heavy metals’ dissolution and migration to groundwater in mining areas.