[A-GE27] 地質媒体における流体移動、物質移行及び環境評価

[AGE27-P03] Vadose Zone Chromium Distributions in Samples Collected from Rania-Khan Chandpur-Kanpur, India

*Vaibhav Deoli¹、Pankaj Kumar Gupta¹、Vivek Dalvi¹、Vivek Nair¹、Anushree Malik¹、Kamal Kishore Pant^2,3 (1.Applied Microbiology Laboratory Centre for Rural Development and Technology Indian Institute of Technology Delhi Hauz Khas New Delhi 110016 India、2.Catalytic Reaction Engineering Group Department of Chemical Engineering Indian Institute of Technology Delhi Hauz Khas New Delhi 110016 India、3.Indian Institute of Technology Roorkee Uttarakhand 247667 India)

キーワード：Chromium, Vadose zone, SEM/EDS Test, Groundwater

Chromite ore processing residual (COPR) is one of the hazardous wastes which frequently dumped in and around industrial clusters in the global space. India has a Rania-Khan Chandpur site, where a large amount of COPR has been dumped in an open atmosphere. The vadose zone of Rania-Khan Chandpur is continued to receive chromate (CrO4-2) leachates and the complications rise the groundwater quality. The main objective of this study is to detect chromium in the surface and deep vadose zones soils and COPR samples. Soil samples are collected from the top surface (0-5 cm) and deep vadose zones (100-105) cm and are used for the Cr and co-pollutants (Mg, Al Si, P, S, Ca, and Fe). We performed Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) mineralogical techniques to understand the solid speciation of the contaminants. A total of 13 soil samples from the study area have been taken for the analysis from which 7, 3, and 3 samples are COPR, surface soil deep vadose zone soil samples, respectively. We found that Mg, Al, Si, Ca, and Fe contents are present in all samples. Chromium varies from 9.6% by weight to 1.17% by weight from the COPR site in a downgradient direction. High Cr content was detected in surface or vadose zone samples from the COPR site of the study area. High Cr in total 8 samples may have more/less leachability and thus may cause further movement of Cr plume towards groundwater. We are confident that COPR leachate continues to diffuse in the vadose zone, however, it is important to investigate other co-pollutants to know their effects on the soil. This study clearly distinguishes the difference between COPR and soils. Furthermore, SEM/EDS tests can be performed for all other hazardous materials in the soil. In future research, suitable microbial-based biological methods would be identified and tested for the Cr and co-pollutants removal from the soil samples.