Field-scale assessment of soil, water, plant, and soil microbiome in and around Rania-Khan Chandpur Chromium contaminated site, India.

Rania-Khan Chandpur site, (Kanpur Dehat, Uttar Pradesh, India), one of the highly Chromium (Cr) contaminated sites in India due to Chromite Ore Processing Residue (COPR), has been investigated at the field-scale. We found that the area around the COPR dumps was hazardously contaminated with the Cr where its concentrations in the surface water and groundwater were > 40 mgL-1, its maximum contents in the COPRs and in the soils of the adjoining lands were 9.6 wt% and 3.83 wt%, respectively. By exploring the vegetation and microbial distribution across the site, we advocate the appropriateness of Cynodon dactylon , Chrysopogon zizanioides , Cyperus sp., and Typha angustifolia as the most suitable phytoremediation agent because their association with Cr remediating bacterial species (Pseudomonas sp. , Clostridium sp. and Bacillus sp.) was strong. Using this remarkable information for the bioremediation projects, this site can be re-vegetated and bioaugmented to remediate Cr in soils, waterlogged ditches, surface water, and in groundwater systems. [Display omitted] • A globally known COPR contaminated site was investigated at the field-scale. • Soil-water systems impacted by the hazardous chromium have been studied. • Only a few plant species can grow in Cr contaminated zone or near COPR sites. • Cr content (up to 9.6 wt%) in soils was one of the key drivers of microbiome. • Selected native plants and microbes can improve soil-water quality at COPR sites. [ABSTRACT FROM AUTHOR]